Like HighIntensity, CytoMel and Needsize have explained. Don't use wrist straps unless absolutely necessary. Try to use an overhand grip as long as possible to gain grip/forearm strength. Once your overhand grip fails you can use an alternating grip (over/under) for continued work sets. I very rarely use wrist straps. Chalk can go a long way in aiding your grip for heavy sets.
The only time I will use straps is for overload rack pulls and shrugs but this is always after my grip has failed. Another possible exercise is heavy dumbbell walking lunges but like I said only after your grip has failed. Hope this helps!
- Screwball