Honestly, I don't know how to make a dress. I may make one but it would get a wrong size or shape. It may look funny also. What about you, can you make a dress?
I think, first of all, I have to buy cloth as per my choice. Then, it would be better if I give it a wash. Some cloths, you know, shrink after washing. Now, squeeze out water and hang it outside on a rope. You better place a clip on it otherwise it may blow away. After drying, press it properly. I hope, you don't need to send it to a lau