I think this is the best build for lulu rightnow. I solo an ez with same amount of item after got my 3th item

You can max W first and then max E, Q for the last. ULt lv 6,11,16 as usual

If you got a hard match up just farrm under the tower which not to hard for lulu, after 2 or 3 item you should be fine in team fights, avoid solo-ing riven, ire and camille if you not far ahead.
If against a darius or trundle just kite them around
Other match-ups, you should doing fine i guess
And keep you ward up cause getting gank by enemy jungler is the last thing lulu i mean this lulu wanna get