Hey man - you've come to the right place. The best guide is this pic attached. I recommend the length of the gap between the two black dots should be about 2-4mm, no more.
The vein you have circled in red is very far from where you will be tying, and will not affect the tie at all.
What questions do you have? I think you have most of the information to do your first tie - and save all that money!
Just wanted to ask a couple questions 1. after the first thread cuts through your frenulum where do you your next tie 2. how do you know that it’s cutting through your frenulum properly 3. If the wire doesn’t cut through your frenulum how do you pull the wire out without hurting yourself or your frenulum, Pics would be appreciated and going into detail would be amazing ? Cheers