Its kind of an annoying thing to lug around with me - its about a metre high and usually travels in a cardboard tube. I've been all over the place with it, had to shorten the tube to get it in my suitcase for going to London this year, and then when you get to a place you still have to carry it and its awkward. So, I made a bag for it, ready for this week's trip to DPC in Amsterdam.
Its along the same lines as the yoga mat bags that I keep seeing patterns for - just a tube with a circle at the bottom to make it a cylinder, some webbing sewn into the seam to make a strap and a cord to pull tight at the neck, I took some pictures as I went along.
First I cut out a rectangle, longer than the tube by about 4 inches and wide enough to go round (very easily round). Then I made the little pocket at the top for the cord to go through (best to do this first as otherwise you'll probably sew it shut later - thanks mum!). Once you've made the pocket then you have a right side and a wrong side, this next bit is easy to get wrong so pay attention! Lay out the rectangle with the right side up. Lay the strap ends against an edge, then fold the other edge over to meet and make the seam - you should have the hem of the cord sleeve on the outside, and a tube with the strap hanging in the middle of it, now pin straps and seam and sew. I went back and forth a couple of times over where the straps were attached.
Time for some maths!
First measure across the tube with it flat. Double that number and you have the circumfrence of the shape you need for the bottom of the bag. So, divide that by 2 times pi (6.283 ish) to get the radius of the circle to cut out. Don't forget to add seam allowance to this. I had a compass to make my circle but a piece of thread and a pencil would do in a pinch. Once you have cut out the circle, put loads of pins in facing outwards, and then sew round the outside, over the pins. Turn bag the right way out, thread cord through sleeve, and you're done :)
I just hope it hangs together for a while, got a few conferences to get to this year!