How do I beat the Heimer?

Don't go poke for poke with him. Just keep killing his turrets. Try to stay at mid-long range when not killing a turret so he can't blast you. If his turrets are dead, poke at him...just make sure his ult+missile blast isn't going to 2 hit you when you poke at him.

I have yet to lose a lane vs a heimer... but he is a pain in the ass. You need to let him push and farm safely under turret. Most mid laners beat him in an all-in at 6. Then it's not half bad.

if you get to pick into him i highly suggest playing syndra not only is she a hard counter for himerdonger i find her really fun to play as a champion and i also start with my W on her now. and beacuse i dont take magic resist runes i usually go chalice but you can also build morllos instead up to you

You must figure out if he is full AP or tanky. If he is full AP, you will have some openings to dive him during the laning phase. If he have more resistance however (hourglass, roa, raptor cloak, negatron) , then diving him can only result to your death. Even with the help of your jungler. Howerver, you will be able to trade with him, get closer and risk a bit more rockets and grenades since they do less dmg.

Then you must figure out if he is going for late game or early game. If he goes for flat AP runes and masteries yes he will fall out late game. So you can farm calmly and not give him some dumb kills. However if he's building late game item (roa, seraph, gp10, hp5 [he scale so well out of hp5 late game..]) then playing passively will just serve his cause.

Last bit of advice. Try to juggle with his positionning in lane as much as possible. Giving up on ground will force him to leave turret behind and replace them by himself. If he manage to nail you to his towers with 3 turrets stacked, then you might need the help of your jungler to break the siege. depending on his build ↑ . Or just keep calm and farm under tower.

Just.....

His late game is generally horrid. can use his spells to keep the turrets down and poke Heimer behind them, but... can effectively counter him best, IMO. You can move his turrets with your satchel, can poke him to submission with your Q and just outclass him in all ways.

this isn't actually too hard to do. Buy lots of potions, target his turrets in laning phase, dodge the blue pew pews and poke when you can

You don't.

Thats why he has one of the highest win rates in the game.

Play if you hit a max range spear it 1shots the turrets and u take no damage from them.

Take flask+4 pots, then destroy everyone of his turrents everytime he places one.

Kill the turrets. Kill them good. It may seem pointless, but he does have to wait on a cooldown to make more. If you use a ranged AoE champion its the best to catch a turret and Heimer in one shot.

take if you're really worried and get to farm waves kappa

Get a bunch of AOE on your team so you accidentally completely remove his presence from a fight.

You could just play and use his towers against him (u can throw them with ur W) :D