Whlen should the particle を be used?

Question:

I just find myself not using it very much in Japanese. Help please

Answer:

If you are doing something to an object. For example:
本を読みました。(Hon o yomimashita)　- I read a book.
What did you do to the book? You did something to it, you read it. Therefore "を” is needed.
バナナを食べました。(Banana o tabemashita) - I ate a banana.
Once again, what did you do to the banana? You did something to it, you ate it. Once again, "を" is needed.

Even things like this:
角を右に曲がってください。(Kado o migi ni magatte kudasai) - Please turn right at the corner.
This one is a bit harder. I don't know at what level in your Japanese studies you are so you may or may not understand this one but it's good to know.
What did you do to the corner? You did something to it, you turned right at it. So, "を" is needed.

I hope this made it a bit easier for you to understand!　頑張ってね！