How do I figure out sizes?

I know I am losing sizes, along with all these pounds, but I am confused by them.  Every company makes everything different so I am finding that in jeans and pants I am able to wear things everywhere between some 18/20's and as big as some 24's.  On shirts I am still wearing many of my 2x shirts, but not sure how to figure out actual shirt size between different cuts and the fact that so many of them have so much give in the material.  What is the best way to figure this out so I actually know what size to look for when looking at used stuff?

I think that this is an ongoing issue. To be honest, I am having a size 10 dress altered and they are having to add 2 inches to the back of it because I can't get it zipped up... That said, most of my clothes are size 6 and 8.I guess I'm saying that mostly I wear a 6/8 or a medium, but sometimes I wear a small or a large... even an XL... The sizes are all over the map. I just keep trying things on and buy whatever fits ... or in the case of the dress if I really want it, I'll take it to my tailor and she'll 'make it fit.' 

Just know you have to spend an inordinate amount of time trying stuff on... I usually take at least 3 different sizes with me into the dressing room. While it can be frustrating, it can also be fun if you don't let the 'size' thing mess with your head. 

Have fun!

I am with Barbara on this one.  As much as I would like to say that I am a 12, (actually I would like to say that I am a 6 lol) I still wear some 14's,  I also wear anywhere between a xl to a med.  It all depends on what you buy.  I love it when I get to buy the smaller sizes but as long as I am losing weight and inches I guess I will be okay.

You really just have to know the brand and how it fits... trust me it gets worse the smaller you are :-)
I wear an 8 and 10 in pants... I have a size 10 lucky jeans thats too small and a size 8 lucky jeans thats too big... different cuts, same manfu... Ive fit into a 6 before as well. I mainly wear a medium in tops but have fit into a small and large... sometimes a large is too small and a small is too large... lol confusing isnt it?

I concur with the other posters.  The size varies and you will wear a range of sizes.  I can currently get into some L & XL dresses and tops, some 16, 18 & 20 skirts and pants.  As much as I hate trying on clothes, I've found it is the only way I can get the "right" size for any particular piece.  I'm shooting for a comfortable 14 all by my 1 year surgiversary but I've come to the conclusion, I'll be in a 14 in some outfits and not in others.

Deb