seconding (i think) what other have said-- find a style you like, one that makes sense to you.. follow it.

i had a term paper torn to shreads by a not native speaker of english-- for puctuation.. i brought in my style book (the economist style book, acutally) showed i had followed a consistant form, and since he acutally read the economist, he re-marked the paper.. by grade went from c+ to A. (mind you, in college, i wrote, and rewrote, and rewrote again to get it right..)
A consistant clear style-- one you copy or devise for your self -- works. the economist style is very different fromt the NYTimes.. but both are very readable.