I was making a shopping bag for my mum yesterday and was dreading making straps. They never come out great, never everywhere the same size, never perfectly straight unless I spend so much time on them. They always make my bags a little less perfect. I starded thinking about ways to make them more perfect in a quick way, and I found it! And thought I let you in on my secrect ;-)
All you need is a metal ruler, you can't use plastic, CAN'T CAN'T CAN'T!!!!
I made a step by step tutorial for quick strap making.
Like I said, you need a metal ruler, of some sort of strip that can stand heat. This ruler is about 3 cm wide and a perfect strap size I think. It's 50 cm long, works easier with this lenght but I guess you can use shorter ones.
BE VERY CAREFULL, THE RULER GETS HOT HOT HOT. SO DON'T TOUCH RIGHT AFTER IRONING!!!!