Beginner in GIMP, how to add transparency?

Since I don't care for most clothes in SL, I want to make some of my own.
I have the templates for the body and clothing etc...

For this question I will stick to shirts.

Anyways, once I make a nice design on a shirt, how do I get parts of the shirt to be transparent, like if I wanted a particular cut for the neck or sleeves? Would it even be possible to make the cut different since SL shirts have that akward looking fade at the sleeves or neck when you try to edit them?
Or if I wanted to make a tattoo, how would I make everything transparent except the tattoo?

I know very little about how to use GIMP. I made a cheesy shirt in MS paint using the templates.

One thing - once I make a photo of something, I do know how to upload and actually put it on a shirt in appearance. it is the transparency thing in GIMP that I don't know how to mess with.

Check out the Texturing Forum - tons of info in there to assist, especially on transparency/alpha channel: /109/1.html

The help file for Gimp 2.6, said to be a "Work in Progress", is at http://docs.gimp.org/en/ .

The Channels Dialog help is at http://docs.gimp.org/en/gimp-channel-dialog.html .

You can add an alpha channel in the Layer Dialog, the help file for which is at http://docs.gimp.org/en/gimp-dialogs-structure.html#gimp-layer-dialog .

If you have a different, earlier version of Gimp you would want to find the correct help for that version.

Also, there's a Gimp inworld group, and there are inworld lessons on Gimp.

Here's a tutorial on Gimp with some alpha channel info in it: http://www.mermaiddiaries.com/2007/03/day-181-creating-clothes-with-gimp.html /

As a beginner in Gimp you'd do well to work through tutorials and become generally familiar with the program before focusing on making clothes for Second Life.

QFT!

I admit that clothes-making is not my thing, but after taking the in-world Gimp class twice (that's a total of 20 lessons plus countless hours of homework) I *still* can't make the button-down business shirt. Tricky project, that. But I'll get it...eventually.

I know this does not belong in this forum, but I've made shirts and bathingsuits.

To get nice collars and sleeves. Make a 2 layer (at least) 512*512 image with a TRANSPARENT background. On layer two, paste in the mesh so you have a guide. On layer 1 draw your shirt. To get nice collars or straps use the path tool. Use a pencil for the rest. Make sure if your straps are thin to widen them a bit as they reach the top of the shoulders. You need to thicken your straps so they don't disappear where the front and back straps meet at the shoulder.

Thanks Ivoba

Just seem to have a mental block on clothes. I made it through gems, metals, animated textures, etc. just fine but this shirt is a doosey....lol.

Yes, plenty of tutorials out there, check texturing tips, or take the class inworld that Cezari mentioned

Making transparency masks using GIMP:

/109/72/189735/1.html

This post was oriented more toward adding transparency to a photo, where the background (to be made transparent) is already nearly white or nearly black.
HTH

There are two easy ways to get transparency in an image or texture with GIMP. First, probably the easiest, is to go the the layers menu drop down>transparency>"color to alpha".....just make sure the color that you want replaced with the alpha channel is the color in the pallet (if not, the change it to the color you want.......it's default is white). The other way is almost as easy (maybe even easier depending on how you work with your images/textures). Again, go the layer drop down menu>transparency>"add alpha channel". Now when you cut or erase anything on the layer you are working with it cuts or erases to transparency instead of the background color.

Give both ways a shot.....you'll see which is best for any particular situation.

Colour to Alpha, or else read up on some GIMP tutorials

Since this was revived, I will add something that might be helpful - you can fuzzy select the color you want to turn to alpha- but only before choosing color to alpha. So, what if you have say a green background (as stated above, it defaults to white)? Fuzzy select, then go to the color window, copy the color value, exit that window, go to color to alpha, paste your color info into the appropriate space- THEN- color to alpha.