Try using a large over sized t-shirt as the base for your dress. These can be found in thrift stores or even in the back of your own closet. Get creative with your fabric choice and try using a sheet or curtain as the fabric for your dress. You can thrift for pretty vintage versions of these fabrics if you don’t have any at home you’re willing to cut up.
Add ½ inch of extra fabric around the edges of the dress for seam allowances. Most patterns already have this included in their measurements, but you will need to keep this in mind if you are tracing a dress for your pattern. If you want to add sleeves to your dress, these will need to be cut as separate pieces from the body of the dress. Cut your dress fabric in a tank-style top and then sew your sleeves on later. Be sure to cut the fabric for the back of this dress as well at this point, using the same method as you did to cut the front.
Follow any specific directions on your pattern for sewing additional sections of your dress. If your pattern directs you to sew something other than the sides first, do so.