I post my pics on photobucket (its free and I'm "frugal") and then insert a link from there to here. It's pretty simple once you know what to do.
Hit "post rely" at the bottom of the thread, just like you have already learned to do. A page opens up to post your reply. Above the box where you type in your message, you will see a series of "buttons"
to insert a picture click on IMG which will place some formatting in the message box. it will look like IMG and /IMG within brackets [ ] To post a website link you would click on URL.
For photobucket, I use "direct link" and copy/paste the location between the IMG tags. You can also use the "IMG Code" (you would not click on IMG button here) or "IMG thumbnails" (also no extra formatting needed). Thumbnails are nice in that they make a small pic and if someone wants to see a bigger pic, they can click on the pic and it will take them to the full size pic on photobucket. If you rearrange and move pics around on the photobucket you may lose the pictures you have linked to elsewhere. For pictures that I have uploaded to my website, I just right click click on the pic on the website and click on "copy image location". Back to the "post a reply" page on skoolie.net and click on the IMG button. The cursor will be positioned in between the bracketed IMG and /IMG. Just hit the "Control" button and the "V" button to paste the picture location in between the bracketed IMG . And there is your picture location... (my picture location info... http://i570.photobucket.com/albums/ss15 ... Silv-1.jpg
placed between the bracketed IMG and /IMG). Click on Submit to post and your picture will show up like this....
This is a thumbnail that you would just copy & paste the link with all formatting included
The first pic was simply cropped. The second pic is a thumbnail. This is the full size picture the others are from. The larger pictures tends to make loading pages on slow internet connections a PITA. I have a slow internet connection (free campground wi-fi) I have have often skipped reading pages because they are heavy on really large, slow loading pictures. Yet I do not post a lot of thumbnails either... go figure.