There are many different career tracks within CPA firms so you should consider what position (audit, tax, enterprise risk, valuation, etc.) you would be after. Most of the entry level positions do not require a CPA license to start and some do not require a license at all, so you could interview and earn your CPA while you work. Alternatively, you could begin sitting for the various parts of the CPA exam so that you have more of a foot in the door when interviewing. It seems that most firms are actively looking for experienced hires now.