There isn't really a set routine on it yet. Personally I would try twice a week to start out and see how you do. You MIGHT be able to go to 3x per week but the half life should be 2-3+ days so you should only need 2x week injections. You don't want too much in your system since it can actually inhibit differentiation (possibly by negative feedback although I'm not exactly sure), but since we 'THINK' it is going systemic you aren't going to have all of it going to the muscles so the dosage shouldn't be too low either. Don't worry about your heart or anything like that, I have studies backing the fact it is actually healthy for your heart in these lower dosages and for up to 12 months! Negative effects were only seen after high doses at like 12-18 months or something crazy like that.
Pick a dosage, try it and see how well it works, there aren't a lot of users out there yet since it is relatively new, although I posted a thread giving some samples away at Professional Muscle dot com and people posted their feedback in there and their dosage schemes. There were some really positive results if I remember correctly.