this guide does NOT tell u how to properly support as lux
your lvl 20
lux support build
first back.. then grabs a
before rushing 
afteru have completed
and 
the final 2 slots can vary depending on the game.. but a good default is
and 
you max W SECOND.. not first
u max E first, and Q last.
the only time u would max W first is if u have very heavily losing lane.
which u shouldnt be doing because u only pick lux into favorable matchups.. if u were to vs hard CC and would need to max W first u shouldn't have picked lux in the first place
kelptomancy and E let you poke your oppoents down you can even throw your auto out beforeyour E reaches its destination and as long as u detonate your E first u still get your passive proc and kelpto
you should also have futures market.
i mean sure if u stuck with lux into a bad matchup then sure u can max W first... but... u shouldn't have picked lux into a bad matchup.. lux isnt a support u blind pick... u only pick her after seeing what support they have.
i have been playing lux support since season 3.
i dont mind u making a guide, but guides are supposed to help people... not give them incorrect info.
lux supports transitions into a late game mage becuase how well her shield scales with AP. and how much her E costs requiring you to get enough mana to spam it.. which requires a tear
if anyone build they way u said they would be completely out of mana past 25 min in any siege without 2 oceans which u cannot guarantee, and they would do next to no damage.. and thier shield would be MUCH weaker. becuase of how well i scales with ap and how nerfed + shielding has gotten.
maxing W first it may provide u a safer early game if u are LOSING, but like i said.. u dont PICK lux support into a losing matchup.