If you have a new account the best way to start it is organically. Start with about 5 follows at a time spaced 15-20 minutes apart, no more than 80 per day. Then the next day do 6 follows at a time, and then 7, and work your way up to 20 follows at a time, 60 or so per hour, 200+ per day.
There is software that can help with building your profile, but the vast majority of it (Basically everything you can find publicly) will get your account banned, so be very careful what automation tools you use.