I'd certainly suggest getting onto the metformin now and perhaps leaving the clomid until later if that is what you want to do. As BG said, it can take quite some time to work up to the required dosage of metformin.

Sometimes metformin alone is enough to start PCOS women ovulating again. Sometimes you'll still need clomid, but being on the right dosage of metformin when you start clomid is one way to ensure that the clomid has the best possible chance of working.

BW