I am just learning how to sew. My wife knits and we have two sewing machines but she doesn't really enjoy sewing. Oddly enough, it is not that difficult and there are lots of great things you can do with even a simple machine.

I haven't done anything like a backpack, but I would start out with a mock up made out of left over fabric to determine the best way of cutting and assembling the pattern. Like anything, you only get better with practice.

I think you did a great job on that backpack. The next will be even better.