Its better that you save it to your computer then upload it yourself, otherwise if i delete it down the line it'll dissappear from your sig........

Right click on the sig and select save picture. then choose your desktop for finding it again easily.

then when you go into your profile use the image hosting in the bottom left. browse to your desktop where you saved the pic and select it, then click on upload.

Then right click on the long text in the box and select 'sellect all' then once its highlighted right click again and select copy. then goto your profile sig box and right click and select paste.

done.