So you just bought a really nice, custom moldable product. Do yourself a favor and take it to a shop to be professionally molded so you can reap the benefits of having it done properly. Your boots are the most important part of your set up so don't cheap out here.
If you bought them online (or not from a shop) be prepared to spend between $40-$50 to have the liners molded with proper toe caps, padding on problem areas, and ultimately to have someone who knows what they are doing to it properly. Plus, if they screw it up, they will replace them for you but if you try yourself and botch it, it will all be on you.