Yo guys I've been using top often lately and i've been wondering when should i roam? Even after i win lane their tower is down and im up in cs if i got to gank another lane my tower is under attack every single time in top lane. So when i go to help out at drag or team fights my top is usually destroyed after the fight by enemy top laner. When is the best time i can go roam and help team without jeopardizing my tower? (this question is for early to mid game stage)
It doesnt really matter if u lose top tower, if you get something else in return. Getting 1-2 kills + drake and or some other turrets is worth sacrificing top turret for. Also you dont really need to roam, thats why u have teleport.
I tend to roam freely after I take the enemy tower. I always grab 
over 
because I love map presence. That being said, top lane feels like the less important of the lanes. In my experience it is the last lane to have its turret down due to people focusing mid and bot (I'm unranked though, so I could be wrong). You shouldn't ignore top once you roam, going back to clear waves should be something you do when there are no objectives being contested or teamfights happening.
Play 
Never Group
Only Split push
Melt Towers
Win Games
Climb Elo
Easy
Usually if you can get a kill or force your lane opponent low or to back then that's a good opportunity. Even if yore low you can back, tp somewhere, etc. That being said if you think that your teleport will secure or earn objectives and kills for your team, its worth letting your tower tank a few hits. Also if your jungler can cover your lane then try asking them if you want to tp bot or something (if for instance they are near top but youre tping bot). If you want to just walk into like midlane and cause some chaos there the same thing really applies, of trying to win a quick trade or assert lane dominance first. I played shen and gnar for a while and they actually really help you to learn when and why to tp place (shen is good for saving teammates and even if you use ult for no reason you dont get punished too hard because you have tp still and gnar's rage bar lets you know when is a good oppurtunity to look around the map for potential tp ganks and stuff). If its really early in the game you shouldnt have to worry too much about losing tower, it will take a lot of damage but if the enemy only has like half an item or so it should have at least half health, and again objectives for your team in return for the lost tower are always great.
