Plain weave selvedge query.

Planning to weave a striped scarf in plain weave. Threading will be 1,2,3,4 repeat, and treading 1and 3, 2 and 4, repeat. My question is how do I thread the selvedge? Do I just double the threads in the outer dent on each side, or the outer 2 dents on each side? I am weaving using a Tencel yarn