Not Updated For Current Season
Info: Lux is a good support/carry character with a low cool down ult and a scouting spell
Masteries: I go with a standard 9-0-21 build, using the flash and clarity masteries.
Summoner spells: I noticed early game Lux tend to run out of mana really quickly so I use clarity to cast more spells for the early feed. Flash is an essential for Lux due to the lack of escape moves she has.
Runes: For reds i use magic penetration runes, yellows for Mana regen, blues for Cooldown Reduction, and More Magic penetration for Quints.
Skill Sequence: I like to get light binding first then max out lucent singularity then get my ult when ever available, then max out prismatic barrier last
Skill Combo: At lvl 1 use Q then go for the illumination bonus damage. When you get your E the combo goes Q>E then basic. At lvl 6 I use light binding then throw down lucent singularity then finales funkeln while they're still snared then explode lucent singularity if they haven't already died. So it's somting like this Q>E>R>E
I hoped you liked my build guide remember to comment and like :)