The use of を with する verbs
 

Are there rules about when to use and not to use を with する verbs?

For example,
電話する
電話をする (I think I've seen both)

使用する
使用をする (I have never seen it with を)

Do some combinations require it and others not? Do none require it but some permit it? Do all permit it and permit not using it?

I figured this was a general enough question for a new thread, rather than to be inserted into the thread specifically for my questions.

I remember wondering this back when I first started and learned 勉強する　・　勉強をする

From my limited time spent reading Japanese, I feel like the を is very often omitted.

Good thread, I have noticed the same thing. Especially the above 勉強する

When you have a word or phrase precedng and modifying the kanji noun, you must use the を unless the whole phrase is well-recognized as one verb. 使用 is no exception.

国際電話をする
国際電話する
Both correct
＿＿＿

Must use を:
薬品の違法使用をする
無許可使用をしてはいけない

Gracias, mi amigo.