I am using a temple for the first time, and it didn't come with any instructions. It seems like I need to weave a couple of inches or so of my project before putting in the temple. Is this the best way to begin?
I wove with scrap yarn to begin my project so that I would have a place to put the temple, but the edge threads are spread wider than the width of the warp in the reed. I think this may be because the scrap yarn is not as fine as my project yarns will be. My project is a scarf using Tencel at 24 epi. I have a metal temple.
I usually start weaving with the actual weft, rather than scrap yarn. I tie the warp onto the front apron rod in small groups (1/2 inch or so) so that there isn't much need to "spread" the warp. Then, when I have woven about 3/4 inch (or even less), I put as much of the temple as I can, usually using only two of the teeth, or so. My temples are wooden and wider than yours, so I have to do this partial insertion; you may be able to put most of the teeth on yours in about 3/4 inch of weaving.
Be sure the temple is set so the base of the teeth are even with the warp width AT THE REED.
For your current situation, just put the temple in the scrap yarn and start weaving with the real yarn and move the temple up after every 1/4 inch. You can unravel some of the real yarn later if the beginning of your weaving is spread a bit more than the desired width (because of your heavy scrap yarn).
Since you are weaving a plaid, you might want to weave an inch or so with just one of the Tencel colors that you will remove later so that the width is completely consistent before you start the actual plaid.