Machine wash (30*C) – I suggest turning the garment inside out.
Use gentle cycle with cold water and a gentle washing detergent.
The dress dries very quickly and minimal ironing is needed. Iron on a low setting; – Please avoid ironing buttons and embroidery
All this will help keep your item looking new and prevent shrinking and fading.
If you want to store it:
Make sure the garment is absolutely clean before storing.
Wrap the garment in the acid free tissue, clean white sheet or muslin as a cover and store it in acid/lignin free cardboard box.
My preference is: acid free tissue to soften the creases, wrapped in a cotton muslin bag and stored in a cedar chest, because I think it also does a better job of keeping out the BUGS.