Ok so maybe this is something that has been posted in here before but in case it has not I wanted to share the way I get my knots nice and tight without rolling the elastic.
First of all I use loop knots-aka Larks Head knot (I have not been able to get the double knots to look as nice).
- cut my elastic the size I need it to be.
- cut my tulle the double length I need it to be
- fold the first piece of tulle (or pieces together if you use two strips at the same time) in the middle. Put your index finder inside the loop the middle of the tulle formed and gather it for and pinch it together to begin your loop knot.
-I now make my knot using my fingers (index and thumb)
-while holding the knot with my index and thumb I loop it though my elastic (that is why I had not yet sew it together). I move my knot all the way to the end of the elastic leaving, 1inch or so before the end, and pinch the tulle while pulling the end to tight it.
- repeat the same over and over again until you have put most of your needed tulle in the elastic. Making sure all your knots and nice and tight close together.
- now remeasure your waist(in case the elastic stretched) and cut it a bit if it's too long.
-sew the ends together of the elastic and continue tying your knots the usual way you would if you would have started with a sewn elastic. This will help you fill the small gap you should have and cover your elastic completely.
***I have found that by doing it this way I don't stretch the elastic as much and reduce its elasticity, I can make waist modifications much easily, it takes me less time, I can space my tulle knots more evenly, and a lot of more advantages.***
I hope I was clear and not too confusing. I can add some pictures if you want and of course I can explain better if there is something you didn't get