But with paper patterns, if you cut out the size you need, you are pretty much stuck and would have to re-purchase the pattern. If I want to save a paper pattern for future use, I will use the following technique.
First, I cut the pattern out using the outermost line, regardless of size. On the straight lines, it is easy; fold on the size you want to use. It is on the curved parts that things can get tricky. I slice down to the size I want to use perpindicular to the cutting line.
This will make small wedges that can now be folded under smoothly. Continue around all curved edges.
When you cut around the pattern, you will need to be careful to not snip the edge of the pattern. That would cut the fold, and defeat the purpose of all that work for conserving.