>I have a bit of a slouch due to sitting down all the time so I don't look very confident. Will I get spurned?
If you come up all hunched over, whisper a barely audible “compliment”, and keep your eyes averted the entire time, more than likely you will confuse and creep the fuck out of the person you approach.
Why?
Because you yourself are acting like you’re in the wrong and have something to be ashamed of, which makes the other person follow your lead and assume that your shame is because you’re doing something with a guilty conscious, and are therefore a potentially dangerous/creepy person to interact with.
No one wants to find themselves with a stalker tat might one day snap and do something crazy.
That’s why one of the more important aspects of approaching strangers, is to do so with confidence and goodwill. If you act like there’s nothing wrong, the other person will tend to follow suit and assume there nothing wrong.
Fix your posture. Learn to speak up. Work out
/Chan’s you wardrobe/restyle yourself until you have some confidence in your own looks. Act like you have confidence and strive to improve yourself until the day it all becomes true.
>Also on another note, what's something I can compliment them on? Hair? Clothes? Body?
General riule of thumb:
Compliment decisions and choices; those all reflect and validate persons personality and their beliefs or likes. They are things the person chose to represent themselves.
Do not compliment static or biological traits. Those have little to do with active will. If anything that’s compliment their parents, or them.
A girl cannot control how big her breasts are, nor what color her eyes are.
She can however, choose what accessories or clothing what she compliments her physical feature with, what style she adopts and how it expresses her personality, and any number of other things that she decides make her representation of herself expressively unique.