You can post it at
www.tinypic.com for free. Do NOT substituate tinypics for tinypic. that takes you to a porno site. The following is from a prior post and should help. Many of us use tinypic for this kind of thing.
At tinypic, use the Browse button to find the picture on your pc. Then click the 'Host It' button. When the page comes back, scroll down and you'll see several boxes with urls in them. For posting here, click in the box for the one with the IMG tags on each end. Those tags are important for displaying a picture here.
After clicking in that box the url should be highlighted. Hold the ctrl key and press the 'c' key to copy the url. Sorry if too elementary, it's hard to tell level of knowledge from a post.
Then in your post, just paste (ctrl v) the url in your post. You can then click the Preview Reply button if you want to see what your post will look like before you submit it. When done, close the preview window and click the Submit Reply button.
I'd recommend your picture pasted into a post be no more than about 640x480 or thereabouts in size. You can tell the size by rightclicking and selecting properties (works that way on mine, anyhow). If you need to resize the picture and don't have software to do that, Irfanview is free at
www.irfanview.com . This is what I usually use. After resizing I also do File/Save AS (rather than file/save or the save button). There I can tell it to save at 65% quality. That significantly reduces the size of the file itself so it will load faster for those on a slow connection (much appreciated if you'd do this).
It's a lot easier than it sounds.
If you want the picture to be part of your signature, go to your profile and paste that same url, with img tags, in the signature box.
Good luck. Post back if you have any problems with it. One of us will be along to help.