Sorry for the inconvenience.. I'll see if we can get more space available for uploading images. Until then, the third party hosing website really is the best way, and you don't need to create an account. After you upload your image (ignore where it says enter your email to save and share) scroll down to the "Hotlink for Forums (1)".. copy that link and paste it in your post and your good to go.
Postimage.org is a good one, but I personally always use Imgur.com
Steps for Imgur:
1) Click "Upload Images" at the very top of the site next to where it says "imgur"
2) Click "Browse your computer"
3) Double click the image you wish to upload
4) Click "start upload"
5) After it uploads, you want to copy the link next to where it says "BBCode (message boards & forums)" and paste it in your post.
Between those two sites hopefully one will work for you. Like I said, we'll try to get more space, but even when there is plenty of space the third party option is superior because image size is limited when uploading to the forum and it also causes the forum to load slower. MTB2223is most likely right, we should just disable the forum upload feature altogether.