Here's SwitchBlade69's Lux build. Make sure to follow the instructions in the Items Chapter, otherwise you may be confused. This build will give you more ability power and cooldown reduction. as some of the other guides have a bit more health, when playing lux, you will always be out of range of minions and other champions, there for no reason for the extra bit of health. If you are caught in a snare or stun, being the only time you are in close combat with other champions, the extra health would be useless. I have used some of the other guides and made mine according to what i felt Lux needed. Hope it helps!

After Zhonya's Hourglass sell Doran's Ring Kage's Lucky Pick to make room for Lich Bane and Void Staff. Then, after Void Staff, sell Mejai's Soulstealer to make room for Trinity Force.
While lux's health is a bit low, cool down reduction from Ionian Boots, and very high ability power. The number one goal while playing lux is to stay alive, staying out of range of minions or opposing champions. doing so will lead you to be a succesful Lux. Hope this guide helps. Banshee's Vail could be used in place of Trinity Force if you prefer. And you can replace Mejai's Soulstealer with Morello's Evil Tome. people when building RoA get first, which is 1325g spent in the wrong direction. While HP is nice, lux really can't escape much (if you miss your Q, you're done)... so that lil extra HP really doesn't make a difference.

Flash will help if you happen to run into a bit of trouble. First off, use light binding to stun the enemy if you are being chased, followed by flash. if you are still being followed, prismatic barrier will give a better chance at surviving while wating on cooldowns. As well as exhaust or cleanse depending on your play style.

The skill sequence when playing Lux:
Staying out of range of other champions, you will throw in lucent singularity to cause a bit of initial damage. followed by prismatic barrier. Light binding, to stun the enemy and then Finales Funekeln to finish them off, if the champion is not dead... Use lucent singularity slightly ahead of the enemy as they walk into it, throw light binding followed by Prismatic Barrier stun and auto attack as you chase the enemy, finishing with lucent singularity as it should finsih them. Your skill sequence should be 3-2-1 or E-W-Q repeated until there Health is low enough for you to ult. If you are being chased with low health... Stun the enemy and if they are still close a simple flash should suffice. Turret diving and chasing enemies are not recommended as your first priority is to stay alive. again the skill sequence is 3-2-1-4 or E-W-Q-R. Hope this helps thanks for reading.

Farming is important as Lux and can give upper hand needed in a battle. Lucent Singularity will allow you to farm minions efficiently, while staying at compfortable range.

Team work is essential in a succesful match. Light binding the the enemy while a team mate attacks and finishing the enemy with Finelis Funkeln. Harrassing the enemy while your "lane mate" is gone, is one of Lux's strengths. Using Lucent Singularity sparingly, and Light Binding the enemy if they get too close for comfort. I highly recommend laning with a tank or melee, this provides you with cover as you harrass from afar. Prismatic barrier+ light binding usually will help your team mate if they are very low on health. recalling often will keep you from getting low on mana or health. Hope this helps!

"This is probably the most essential part of this guide to read and understand.

Lux should always be picked when your team needs range and AP. If your team doesn't have a melee carry/dps - you shouldn't play lux - see, the enemy team will want to kill you no matter what... so if you have melee dps to protect you - they can't. But if you don't have melee DPS - that consists of stuns, slows, knock ups, cc and lots of dps... then you will get focused so fast in team fights your head will spin, and you will just suck.

You're going to be thinking "I need HP, I need survival" - STOP. You cannot build lux survival and carry. If you don't start playing even more passively in team fights, and I mean super passive.. then you're going to get focused down, generally annoyed, and hate lux for being so fail."

-shm0