1. **If I was… is a colloquial alternative to If I were….**
In speech, many English people say If I was…, but If I were… is held to be grammatically correct. It is better, therefore, to stick to If I were…, as in these two examples:
‘If I were you, I’d fill the tank now so that we don’t run out of petrol.’
‘If I were to call in on my way home from work, would that be all right?’