Heat welding is one of the things I really like doing in this line of work. As far as creativity goes, the sky is truly the limit for designs that can be cut and welded into linoleum and vinyl floors. You can alternate flooring colors and patterns as well as colors of welding rod. The short version of "how to" is to butt your seams but not too tightly. You then carve a groove along the seam with a specifically designed grooving tool (different types are available) melt the rod into the groove with a heat welding gun, and then (for most products you wait for the rod to cool)simply trim the rod flat with the floor with a specifically designed "skive" knife. (This is usually done in two passes to avoid a concave profile to the welded seam.)