The quick and dirty way to pull the pulk is to simply fix ropes to the front corners and tie the ropes near your waist. However, if you get on uneven terrain, contours, and a generally bumpy route, you will do better if you fix fairly rigid poles in place of the rope. The poles could be made out of thin plastic water pipe, thin fiberglas, thin metal tubing, or even thin wood such as bamboo.
This is especially true of you are doing any downhills. As you start to descend, if the pulk is attached by simple ropes, it may slide faster than the puller is, and it will run into the heels of the puller. Rigid poles will prevent this. Also, if you travel along a path with side to side bumps, the rope-attached pulk will tend to flip over. The rigid pole-attached pulk is much more difficult to flip over.
Once you get everything rigged up, but before you put your load on the pulk, use some kind of anti-stick compound to prevent icing on the snow surface of the pulk. That could be spray oil, ski wax, or silicone lubricant.
–B.G.–