I know that you have seen it Patricia but I will add here what I put on Jeanona's thread..
...you can use virtually any graphics package.
The clothing is only 2D, it is just a matter of mapping an image to a layout.
If you look at the UVW png files, you will see the layout of each piece of clothing. It represents the full possible extent. If you lay your "cloth" on it, where there is no "cloth" the skin will show through.
To create a height map, which, gives your clothing more of a 3D look, the instructions are in the main topic.
I used the most basic of software (yes, I know, it looks like it, lol) and, of course, the better the software the easier it will be and/or the better quality you will obtain but you don't necessarily need high-end software.
ok, I'll add, as an example...
I mentioned the garter belt above so I will use that.
It helps if your graphics product supports layers but most everything does now. I would add that everything that I have produced before was done without using layers but it makes life easier.
In TEX mode in Achat, if you specify the model you want to use and then...
...select garter belt
...select "Load diffuse"
...specify the UVW file garter_belt_f_uvw.png and when you open it you should get something like this...
this will show you what the full extent of garter belt will look like when it is on the model. Now, it is essentially two pieces, one on the left and one on the right but they are mirror images and you will only be able to specify one of them and it will replicate that automatically on the other side (I will add that some garment UVWs do not have mirror images but are the full garment). You might also refer to this to see how the 2D layout is applied to the 3D model.
So... go to your graphics product and load that image in... garter_belt_f_uvw.png
Create a new layer and design your garter belt. Remember you are creating one side which will be mirrored. I have made it easy so I can show you quickly and have just thrown a red square of material at it. Also, note that, where there is no material, there will be bare skin showing on the model...
Get rid of the original png ...
...and save/export your garter belt under an appropriate name and as a png (note that it is the same size as the original png and, in the case of the software I am using here, the transparent area is checkerboarded).
Then go to your model and
...select "Load diffuse"
...specify the png file that you just created and when you open it you should get something like this...
See the marks on it?
That is the effect of the Height Map for the default garter belt because it is still loaded.
You can see that you have to create an appropriate height map for your garment, in order to simulate a 3D effect.
However, while you are working on the basic garment itself, if you select "Load height map" and specify the same png asyou are using for the Diffuse, then it will get rid of any default height map that may cause confusion.
I'm not going to attempt to explain height maps here but they are essentially generated from the garment that you have already created. The process may seem complex at first but, once you get used to it, it becomes almost second nature, although it can take a lot of time to do properly.