looking to start my cycle soon and I just wanted some advice about pinning. Ive done it before but I think although successful I think I missed something

I know enough to draw from the vile and cleaning both the bottle top and the injection site with separate alcohol swabs. However when I inject am i suppose to pull back on syringe until some blood appears and then inject?? I feel like a dummy asking so be gentle. I just dont wanna make any mistake