i actually have a relatively weak double overhand and hook grip... so i dont ever bother with those grips on any heavy work...
when im trying to get it up, which i will be soon, i do lots of static holds at the end of my deadlift sets... just try and hang on to that last rep as long as possible...
power shrugs also help, i was up to 5x405 on those with no straps, using a mixed grip... its probably not the best for my arms' aesthetics though...
also i will do some high rep wrist curls and i also feel that reverse grip barbell curls help to some extent...