It is not unusual to find people complaint about how hard Kanji is when learning Japanese. Kanji is something borrowed from Chinese characters, while Chinese characters were designed for Chinese language, therefore it is not perfectly compatible with Japanese language, that caused some problems.
As a Chinese, learning Kanji is difficult in other ways. Generally, there is only one prounciation for each Chinese character, probably less than 10% of them contains two or more prounciations but it is so most of time when they mean something different (eg. 長: “cháng” means long and “zhang3” means grow). In Japanese, however, there are many prounciations for one Kanji even they mean the same thing (eg. 食: しょく,食べる： たべる both mean “eat”), and most of time they are multisyllable. As I could recall from a blog article, the function of Kanji in Japanese is not phonogramic like Chinese do, it acts as a symbol that tells you the meaning when a group of Kana are coming together.It is quite like depicting a crossed cigarette symbol instead of writing “No smoking”, but each time you read it “no smoking” when you see it. Kanji is more identifiable than Kana. It is interesting if you learn Japanese but cannot tell the meaning of Kanji, as they are supposed to improve the reading effeciency.
When I was a child, my school teacher tought me how to remember this character “贏” (win, reads “yíng”): break it into “亡口月貝凡”. She talked about this only once and I can still recall it. You break one complex character into simpler parts and form them again, your life will be easier. After all, most simple parts appear in many characters repeatedly. If you can remember a 8-letter word like “Japanese”, why can’t you manage a character with only five components?
So here we are.
Chinese Characters
Traditionally, Chinese characters are categorized into 6 groups. For simplicity, I categorize them into 2 groups: basic and compound.
Basic Characters
Most basic characters contain less strokes. Generally they refer to natural elements, body parts, common animals or concrete objects, like the sun, the moon, trees, etc. Most of them are pictographs or simple lines. As they are pictographs, you can think them in a pictographic way.
人（じん）：human
刀（とう）：knife
口（こう）：mouth
日（ひ）：sun (drawing a circle and a dot in the center, later the curve lines were replaced by straight lines.
目（め）：eye (drawing a “standing” eye). Also used when counting ordinal numbers
土（ど）：clay, ground, land
子（こ）：child
女（しょ）：female
手（しゅ）：hand
木（もく）：tree
火（か）：fire
糸（し）：silk
言（げい）：speech, talk
雨（う）：rain
力（ちから）：strength
山（やま）：mountain (dipicting a mountain with three pinnacles)
川（かわ）：river (depicting a river )
心（こころ）：heart, mental activities
衣（ころも）：clothes
水（みず）：water
金（きん）：metal, gold
車（くるま）：vahicle（Depicting a standing vehicle with a big wheel in the middle, where curves were replaced by straight lines. Any vehicle with wheels, except airplain or wheelchair can be called a 車）
月（つき）：moon
肉（にく）：meat （When 肉 is used as a semantic part in a character it looks very like 月, like 肌- muscle）
示（し）：to indicate, direction
Indicatives
上（うえ）：up, above（indicating the position above the line）
下（した）：down, below（indicating the position under the line）
左（ひだり）：left - the hand (the left-top 十-like symbol) holding tools，工means tools
右（みぎ）：right - the hand to put food into your mouth口
白（しろ）：white（color of the sun日）
自（じ）：self （originally it means the nose, indicating what is infront of the eyes目. When you introduce yourself, which part of your body does your finger point to?）
If you understand the reason, you will not confuse口, 日, 目, 白 and 自.
The are not too many basic characters, however, most of they are the essentail part of many compound characters. If you get familiar with them, you have mastered 60% of characters, theologically – (Basic characters are supposed to occupy 20% of entire character set, and they are half of 80% compound characters.)
Compound Characters
Compound characters are formed by two or more parts. Most of them (80%+) are composed of one semantic part and one phonetic part. A small portion of characters are composed of both semantic parts, while some components are semantic and phonetic at the same time. The semantic part indicates a general meaning, and the phono part tells how it should be pronounced, in Chinese.
人（じん ）：Human activities. It is also written as “亻” (at the left), “ㄦ” (at the bottom)
休（きゅう）：a man lying on a tree, must be resting
兄（あに）：older brother is a man with a big mouth
見（けん）：a person（bottom）with his eyes open, that means to see
僕（ぼく）： servant, I（in a casual way）
Others: 伝, 何
女（しょ）：Female related, also refering to negative mental qualities. Can be written at the left or the bottom.
好（好き：すき）：good, to like. It was considered to have a daughter and a son (子) it must be something good, and you will like them very much.
Female relatives:
妻（つま） wife,
姉（あね） older sister,
妹（いもうと） younger sister,
娘（むすめ） daughter
Activities related to female:
婚（こん）marry
木：Trees. Most names trees contains this part.
東：east（Depicting the sun 日and a tree木, indicating the direction where sun rises）
本：root （indicating the position of the root in a tree 木. In Japanese it also means book）
机（つくえ）：Table. In modern Chinese it is the simplified form of 機, and几 is used to mean a small table instead. So sometimes I am confused.
Other characters with this component: 楽（らく）,happy; 棚（たな）, shelf; 桜（さくら）, sakura, 校, こう, school.
走, 足, 辶：走：walk, run, 足, foot, 辶, walk. Thought they look similar and mean something similar. They mean something related to walking, the road, the distant, etc.
起（き）：getting up
違（い）：different, against
遠（えん）：far
近（こん）：near
速（そく）：speed, quick
遅（ち）：late
迎（むかえ）：to greet (when someone arrives)
送（そう）：see someone off, farewell, also means give something to someone
道（みち）： road (首 means head and it refer to a person. )
週（しゅう）：week
示：Religious related, like god, ceremony. Can be at left or bottom
神（かみ）：God
祝（しゅく）：God is with your older brother? Must be blessing.
祭（さい）：A rite. The upper-left part “月” refers to a meat, the upper-right part refers to a hand, and the bottom “示” refers to a religious activity. So it depicts the ceremony to serve a sacrifice.
礼（れい）：Originally means the “rules” in a religious ceremony, and now it means the ways of manners.
祈（き）：Prayer
火（ひ）：Fire. Can be at left or bottom . When it is at the bottom it is usually written as four dots.
赤（あか）：red（color of burning clay. I might be wrong in this understanding but whatever）
魚（さかな）：fish（Actually the four dots below is not the fire to burn the fish, it depicts the restless water where a fish is jumping out from）
熱（あつ）：Hot. When it is hot it is 熱い（あつい）, and if you are zealous, your heart is hot, so that will be 熱心（ねっしん）.
雨（あめ）：Rain or raining. This part indicates natural phenomonon, not limited to raining.
電（でん）：lightning, electronic. This character is used in many modern appliances as they are motivated by electricity, eg 電話（electronic speech - telephone）, 電車（electronic vehicle, in Chinese it refers to trams and in Japanese it refers to trains）
曇（くもり）：In modern Chinese it means Epiphyllum and in Japanese it means cloudy – Actually cloudy is its ancient Chinese meaning. “The sun is above the clouds(雲、くも)”, makes sense?
雪（ゆき）：Snow, that goes down to a horizontal mountain
金（きん）：Gold, metal or something valuable. Most characters related to metal contains this part.
鉛（えん）：lead（鉛筆、えんぴつ refers to pencil althought a pencil does not contain lead）
銀（ぎん）：silver（銀行 – bank）
鑰(かぎ)：keys
釣（つり）：to fish（if you go fishing you need a metal hook）
Common Phonetic Parts
Some phonetic parts occur in Kanji for many times. As they are phonetic, similar prounciations occur amongh them.
隹：Birds. This character is not used in Japanese or modern Chinese. It reads “zhuī” in Chinese.
曜（よう）：the names of weeks, eg 日曜日：Sunday（にちようび, sometimes I wonder why the same character “日” is prounced differently ）羽（はね）：feather。In Chinese, 翟reads “dí”, means pheasant, with long feather. With “日” (sun) makes it a compound character, refering to the glorious sunny light, also refering to the sun, the moon and stars.
集（しゅう）： collect
“Many birds resting on a tree” is what it depicts. It refers to collect something (集まる、あつまる) or a collection of something, like essays or photos, poetries, or a business corporation (集団、しゅうだん).
推（すい）： push. （The left symbol is hand）
雑（ざつ） ：Something that is mixed with different kindes. Like 雑誌（ざっし）, magazine, the book that contains many articles.
寺（じ）：means “temple” – “A temple is a one-inch (寸)-land (土) ”. Most characters with this component reads しorじ.
時：（しtime）
侍：（じservant）
詩：（しpoetry）
If you have more characters difficult to remember, please suggest and see whether there is a easy way.
Useful links:
Chinese Etymology*** (Very good)
Chinese Etymology Home Page
Japanese grouped by radicals
http://dearbooks.cafe.coocan.jp/kotoba13.html
A Chinese blog with good illustrations:
字源教學舉例（十四例） - 漢字乾坤網─華語文教學、漢字教學、漢字數位化、兩岸 語文 - Yahoo!奇摩部落格