I am very new to this so any help would be greatly appreciated!

so heres the thing, I am only 19 years old and my hairline is receding very badly in the temple areas.. I understand that I could prolly conceal it for another couple of years however the thing is I feel like if i just make the transition now it will be much smoother given the lesser amount of desperation....

My goal is to only fill in the temple region with 2 triangle type shapes... (Partials).. unfortunately I know very little about hairpieces... I see that this website will make partial units however they cost the same as a whole unit.. so common sense tells me to buy a full unit and cut out the shapes my self? this way even if i mess up I can just cut out more pieces... is this a viable possibility for me? also what advice would you give me as far as how to cut the lace, what type of style to ask for, and which type of glue to use seeing as how small the units are?

I really appreciate the advice