register at a website that will host your pics. i use www.photbucket.com and i've used www.aquaticphoto.com it might be photops? hmm.. i dont remember. anyway you go there and you can upload a pic to their site. you click browse and find where you saved it on your computer. then it will load it on to their website. on photobuckt it will give you a link to the blahblahblah[img] file which is what you want to copy and paste into a thread.
or you can right click the picture (once its hosted) click properties and it will tell you its webadress i.e. photobucket.com/user/wastememphis/something ig uess then you can highlight the web adress then come to a forum and click the picture thats yellow and has a mountan on it. then you pase the link in there and hit ok.... that should work. hope this wasn't confusing.