Be careful when using Ambush near enemy turrets, as turrets can see invisible units.
It is always good to use Ambush to scout brushes and to look for enemies.
Twitch can be very good at chipping away an opponent's health with the true damage from his passive. After hitting an opponent a few times, throw your poison vial (W) to hit enemies at long range and add two poison ticks, but more importantly to extend the amount of time they are taking damage from your poison.
Twitch'sAmbush has a timer. Watching the timer is very important when using stealth. Twitch is very good at scouting ahead of his allies while stealthed.
Buying an Oracle's Elixir of your own allows you to counter enemy Vision Wards, but simply playing less aggressively can prevent getting hurt or killed by enemies who are using stealth-countering abilities or items and gives you the advantage in gold.
Spray And Pray is a very good ability to use during teamfights, because you can hit all 5 members of the opposing team.
At high levels and assuming that you are a skilled Twitch player and a skilled jungler, you can move Twitch into the jungle. He is weak when it comes to farming in the jungle for long periods of time, however, his ganks with red buff go unparalleled.
Twitch can function as a attack damage carry in bot lane as well, and is best supported by a character that can hold the lane 1v2 while he ganks.
When ganking, Ambush should be used early, so as not to be caught by regular wards on your way over. When you arrive at your destination, if your stealth timer is low, sit in a bush and wait to re-stealth prior to jumping on your opponent.
At the start of the match, try waiting until the enemy jungler finishes killing blue, then kill him. If successful, this provides a substantial early game lead and can shut down junglers that scale into late game(Amumu, Olaf, etc.).
If you take Ambush first, use it sparingly so that you don't run out of mana early game.
Taking Ambush early game allows Twitch to check bushes without taking too much damage and allows him to counter jungle more efficiently.
If you take Expunge first, use the damage to farm effectively. Do not use it to harass unless you have six stacks of Deadly Venom otherwise you will run out of mana trying to harass and farm at the same time.
Keep in mind that it also procs on hit-effect such as life steal and critical strikes, allowing Twitch to wipe out your team single-handedly.
Very few ADC's can match Twitch's power with a full build , if you want to duel him you must be way more fed than him or be a APC or assasin , else you will not be able to match his damage.
When Twitch is no longer seen in lane, let your allies know by calling mia/ss, lowering his high ganking potential with Ambush.
Due to his low health, hard CC such as stuns and snares are devastating to him.
Twitch's late game power is extremely high, as he can burst down entire teams - don't let him get to that point!
Twitch can easily backdoor as Spray and Pray lets him outrange turret , this however leaves him somewhat weaker , as he is loosing the powerful damage boost from Spray and Pray engaging right after he will be easier to deal with.