Cleaning an image
We won't do any more layering for now, as this is just one a component image (an image that will be manipulated, pasted and and then manipulated again in the final work).... we will proceed to clean it, IMO, the most annoying and tiresome part of doing a sig
1. choose the top layer (the one with the actual image)
2. Choose the magic wand (aka Master cleaner

)
now, this tool is one of the best to select regions of an image, and will simplify the selection in places that are hard to select, just remember, it is almost useless im parts with small details (sparks, or areas with too much colors and small portions of them), it will suit us well, as almost the only color we will have to get rid of is white (hence why i picked this image

)
3. select the white color, or the areas you want to remove
4. right click and Edit>Clean... or just press Ctrl+K (personally I prefer this last method, as sometimes you have to do a really fast job, and clicking slows you down

)
5. in the end, you'll see that now the picture is cleaned and its completely transparent. Yeah, those grey blocks in the background mean that it is transparent
TIP: when you need to finish quickly, use the rectangle selection tool to select big areas of the image, just be careful to not to take down any part of the image you want to preserve
TIP#2: when you see that the rectangle selection tool is too risky, and the magic wand is taking you nowhere, then it is time for you to use the lasso tools.... just zoom in, and selext those tough areas by drawing a selection that suits your needs
__________________
Made with the GIMP