Honestly I believe the guys here are way too optimistic, many delusional.
If you are a 3/10 or perceived as such the best thing you can do is to realize that you have to put some work to improve yourself, only once you reach a certain point you can aim at fvcking, yeah fvcking as bible belt said...aiming to date is basically embracing someone else mindframe.
If you problem is being short nothing much you can do, if you're skinny, fat or skinnyfat hit the gym and fix your diet and life style, if your problem is lack of self esteem do something that will fix it, either hit the gym and get in shape or get a hobby that will mold you into a manly version of yourself.
There are no such things as being a 3 but become a 7 out of nowhere just because you "decide" to be more confident, your level depends on the value you provide physically, mentally and personally.
If someone thinks that "confidence" turns a 3 into a 7, he should also believe that installing windows 10 on a comodor64 will turn it into a alienware gaming pc.
Confidence is the result of victory, is the knowledge that statistically you score high, its a conseguence of success not a random item created out of warm air.