If you are lucky, your snap peas will be so tender that you won't have to perform this step at all and can just toss them in the wok without any preparation at all other than a quick rinse if you may have pesticide residue on your snap peas.
Green Snap Peas and Snap Peas Strings removed from them
If your snap peas aren't quite that tender, and even if the pods themselves are tender, you may find that you want to 'string' the peas - which is a quick removal of the very end of the snap pea pea pod along with the exterior rib (the 'string') which runs the length of the pea pod. If there is a fibrous string there, you'll know it as it will tear off of the pod as you pull off the very end of the pea pod. If it doesn't tear off, it isn't fibrous and stringy enough to worry about anyway!
You don't want to cut or break the peas or shell them, so your preparation is done at this stage, and the peas are ready for the wok.