How to build your own

You will need
A needle
Thread
225 ish grams per square metre canvas though I'm thinking about making it heavier 
A safety announcement
Scissors
A tree trunk
A 1.3kg hammer
Hardware I'm thinking about reducing the diameter 
Sharp as sh*t scissors
Exacto 
A pen, pencil or chalk 
A piece of wood or a desk
A zip 21cm or 20
A ruler or a metre stick 
Pins
Nylon strap 
Ear defenders 
A sewing machine. I've never used a sewing machine. If I do use a sewing machine I should secure the ends - reverse the start or use a lock stitch or tie the ends  
For when you go to a workplace: bank card, keep cup, house keys, a bagel, water, notebook, mandrils, thick piece of material to keep everything clean you can also try a piece of wood or card board
sandbag

What you can do
0 Clean the work surface
1 Take your material 24 ish cm across. This will be a good width because it matches the length of the zip
2 Cut two pieces about 40cm long
3 Install the zip at the top of one side. Think how could I try and make sure this doesn’t come apart for example using a double line of stitches or using a backstitch. 
There is a way of fitting the first half so the stitches aren't visible from the outside / on at least one side of the zip BUT you are probably going to want to  add a line of stitches right over the top. This could be done at the very end. You can use a blanket stitch to go over the rough edges where you fitted the zip. You can do additional complete double rows of stitches as a back up.  
4 Then you are going to fit the hardware on that side. You need a spacer to make the hardware fit correctly.  Fold over the ends of the zip and measure the distance. It is going to be 20cm to between the ends of the zip . You want the centres of your apertures to be 35mm from the edge of the material at each side all of which means there is going to be 130mm between the centres of the apertures along the top and along the bottom. Make a template 2o0mm wide which you can fit between the zip ends and 35mm from the top . it will be 130mm between the holes and 35mm from the side lined up with the zip ends  and mark the position of the top holes with chalk or a pen. This will also be the position - side to side - of the bottom set of holes.
The next thing to do is fit the first two pieces of hardware at the top.
5. You are going to mark the holes and cut it out with exacto then  you can slot in the hardware 
6. Then Fold over the material at the bottom . You can iron in or pin a fold to help you. Then you can mark the position of the lower set of holes mark the circles with a pen cut with exacto and slot the hardware in 
7. then using similar methods you are going to mark and cut the other 4 aperatures .  
No you are probably going to cut through the material so you can fit the hardware. 
6. Then go to a workshop 
6 Then take a hammer and a tree stump and smack the shit out of that hardware. To fit the hardware push it on (using the circular mandril perhaps) And hit the other mandil  with a 120z hammer, push it on again, then hit it another 3 or 4 times . Try not to hit it too hard et al or it might crack. Consider finishing it with a small hammer. If it cracks you can take it out by hammering a spike between the plates
6d. Then you can mark the positions of the other holes . Use a piece of A5 paper
7 Then you can fit the hardware on the other side
8 Then you can fit the zip on the other side. Do lines of stitches inside first and then another set on the outside which will be visible. You can use the width of the zip to measure where to cut the material
9 Now stitch the sides. There is a 2mm difference between a stitch on the inside and a stitch on the outside 
10 Cut off the extra material and take it to the recycling centre and do a 'blanket stitch' all the way up the sides In fact to stitch the sides, what you do is cut a piece of thread and think about OK how could I make sure this doesn’t come apart. How long should it be? For example/ Then stitch that thread at the bottom (becuase it’s at the btoom) and stitch over the same place a couple or three times leaving a bit long at the end then stutci up the sides using what they call a running stitch I guess then back I guess then stitch ove rht example please twice or there times until it holds then you can tie end ends maybe 3 times idk. Then what you can do is theoretically cut off the excess leaving the zip in tack t then stitch up the sides using wha they call a blanket stitch then the inside of the zip can stay in place by being pushed there???? the safety annoumtnet can go in the inside 
11 The safety announcement will go in at the side 
12 If you were me you could hammer an article number in binary & add that to a spreadsheet 
13 You can embroider a map of bike routes in your favorite city 
15 Cut 10mm cotton webbing & stitch the ends so it doesn't come apart
Add some tape on the inside edges 
16 test it



I think you can just stitch up the sides symmetically and then to tidy up the zip on the dodgy side do a closer in stitch and then just push the ends down into the pouch to make it I guss web you are doing the side stitches you can draw a line on both sides and measure its the same distance pin It’s fine to do stitched over the top Use 1 stitch to hold it down ????