I think the most important thing to being a good link is using projectiles in order to hit your opponent with thing other than projectiles. No likes a spammer but you have every right to keep using your projectiles until you make an opening, then once you learn a little about that next is learning the time of shffl nairs and back air combos and shield pressure. I say projectiles first because approaching raw with young link is tough so learn to approach with projectile that lead into nairs and back airs or tilts. well spaced tilts are really handy. and if youre a flashy player learn some bomb swag. double bomb down air you can throw youre bomb in any direction and catch it. learning about boomerang is really tough, any young link knows the struggle of catching the boomerang mid combo and havin the combo or edgeguard ruined by this wonderful projectile. If you dont know there is ways of avoiding the boomerang catching animation. like catching it mid attack or mid dash (running does not cancel animation). If i throw a boomerang on shield i dash forward to catch the boomerang and throw again it can be quite quick and they are likely to jump the second time which can be read or reacted to by aiming boomerang upwards. then once you are good at putting on damage learn to edgeguard or get downsmashes/downairs cause kills are hard. ummmmmmm thats about it off the top of my head