Greg is right, figure out your weak areas (foundation, framing, HVAC, Plumbing, Electrical, etc.) and rank them in a list. Start taking courses in those areas and reading the questions of other on this forum in those categories.
Get yourself copies of constructions standards, code books, local codes, etc. so you have them on hand(preferably digital versions) when needed. Alternatively look at the link library here on NACHI for reference material.
Figure out your reporting software and download a trial copy to look through. Also download as many examples of reports as you can get your hands on, especially from your competitors. Start writing out how you want to report on common issues in the home, it will help you figure out your preferred style of reporting.
Call every competitor you have and ask them for the cost of their inspection. type what they say and don’t ask follow-up questions. You will quickly see who is professional and who is not.
All of this is market research and is invaluable when starting a business.