I like to take a pic of the fabric. Then put it in your pc. You can print off this pic onto copy paper. Then use your template and find a good spot and cut it out of the paper. You can repeat this as many times as you like. I feel you can get a good idea for what it will look like if you use at least 3 or 4 paper blades.
You can sew and iron the paper version just like the fabric.
This way you can test out your fabric without having to cut it. You can play with finding good places on the paper version before committing to the fabric.