Asking for the pay that I want to get

I am currently working part time as an esthetician and am now having the opportunity to do a new procedure at weight loss clinics that works great. My friend and her business partner are hiring me. I want to ask for 40/hour but I am scared to do it. Here are my models:

C new position
T There is no way they are going to pay me 40/hour
F insecure
A keep quiet about what I really want
R don’t ask for the pay I want and take what is offered

C new position
T I need to prove I am worth 40/hr
F driven
A work harder
R say I want 40/ hr

I would like to come up with a different feeling than driven I want to feel confident and motivated I think I feel insecure because I am also thinking the thought that this is new for me and I don’t fully know what I am doing but I do believe the procedure works, now I want to believe that I will work effectively and really crush this.

C new position
F confident, motivated
A provide great value as an employee/provider
R ask for 40/hour