Welcome to the forum . . . you have come to the right place.
The best way to proper form is more a combination of many things not the least of which is experience.
Watch experienced (or pros if you have some around) shooters and emulate them. (join a Field Archery Club) and while shooting with them, if you are doing something wrong . . . most will freely offer advice. Sometimes even brutal[:'(].
Practice . . . but as you learn, you will come to know that "Only Perfect Practice makes Perfect." Shoot often but don't over do it. Don't practice Bad Habits . . . they are difficult to break[:@].
Equipment is only a part of making an archer. Buy the best you can afford that you can handle with unquestionable confidence and be satisfied with it. [8D]
As for the Peep vs No Peep, I shoot with a No Peep and ANYTIME my form slips, it reminds me without hurting my feelings. And it has increased my accuracy a great deal.