As the great Walter Sobchak once said, "are there no rules??!!"
If you are speaking about a hypothetical situation, you should use "if I were," not "if I was." This is called the subjunctive mood. For example: "If I were you I wouldn't neg-bang me just for passing along a helpful tip, though you probably will anyway."
There is a tricky distinction made in certain situations where "if I was" is correct, which is discussed at http://www.cliffsnotes.com/Section/Which-is-correct-if-I-was-or-if-I-wer.... You use "if I was" when the statement is indicative about the past rather than hypothetical. For example: "If I was rude in offering my advice, then I will gladly accept your neg-bang." That statement isn't hypothetical, it is indicative.
Take care, and may you never split your infinitive.