take your picture and put it on your desktop
(you on pc???) if so good right click the thing and open with mspaint
one the image opens in paint go to the top menu bar and go to image->stretch skew
put in something less than 100 in both the vertical and horizontal box, put the same values in each, repeat until the image is 1/4 the size of your screen,
save as whatever,
go to
www.imageshack.us <- click that and go to browse, find your image, and hit the button that says 'host it'
from there it will stall for a sec, then sooner or later you will get a full page of links you can use for various items, go to the 3rd or 2nd from bottom where is says 'view image' and copy that full adress in the box,
come back to wherever you want to post it, and dont use hte quick reply it doesnt have the tool you need, to to 'post reply'
in there over the top of the the text box there will be some icons, look for a yellow box with a picture of a mountain on it, if you hold your mouse over it it will say 'post image' or something allong those lines, click it and you will get a new little window, replace the http crap thats in there with the link you copied, Hit ok.
now you have what looks like www.whatever[IMG/] in the text box.
submit post, and if it doesnt work just edit hte post and put a different link in between the [img] brackets, if you use the same computer your pictures will be saved on imageshack for later use under 'my images'
hope this helps, you wanted a straight walk through so thats it.