First, using yourself or a mannequin, do a rough measure. How long does it need to be? How high? If your heights vary, where do they very? Use those measurements and draw a rough draft (not to scale) and insert those measurements on your paper, and take any additional ones you may need.
Hopefully using the image above will help you understand what I'm saying. Once you have that, sketch the image (to scale now) on newspaper, or any other large paper that will fit.
These are your templates. Test fit to your mannequin and yourself.
The long rectangular piece is the bottom. The other is the sides. You will need to cut two sides, possibly three (one for the center) depending on how big your pack is. I used foam board because I had it lying around. Cut all three out. Set the bottom piece aside. We will use it in part two. Cut out the bottom piece in poster board.
Very carefully, and with lots of patience, hot glue the poster board bottom piece to your two sides.
Test fit. It is important to continuously test fit so that you can make corrections early on. It would really stink if you made your entire backpack, and then it didn't fit correctly.
Now, using a flimsy measuring tape (like one for sewing) measure your top piece. I did mine in sections so I didn't have to bend the poster board too much. Make sure you number them so they don't get messed up.
Next, hot glue those in place. Patience is key! This is an absolute pain. And, I burned my fingers multiple times. But, the skeleton of the pack looks fantastic, so I think it was all worth it!
I also added a string of hot glue along all of the seams so that the poster board wasn't so flimsy near my sections.
This is what you should have so far
Next time, we'll add details. Unfortunately for you guys, I'll be in Vegas next week to celebrate an early 30th birthday (mine!) so I won't have this up until probably the week after. I'll make it extra long though!
Until next time, keep cosplaying! Any questions, comments, or requests, leave them below!Instagram