To post an image you will firstly have to edit your image to ensure its not going to be to large or small or that the file size isn't too large. Once that's accomplished you will then have to upload the image to an FTP site such as Photobucket, Image Dost, TinyPic, Fileshack or Image Hosting.
When posting images it will be important to consider the size of the image you want to post. Too large an image and it will swamp the post and too little and it’ll look insignificant.
From experimenting with image size I’d say a 400 x 400 pixels size would be ideal, though going down to around 200 x 200 will be okay. Anything under or over these dimensions will appear too large or too small. And as BuBBy points out below, convert your image to an image type such as GIF or JPEG which tend to be of a much lower file size than say BMP or PNG. Also you can further reduce the file size by reducing the resolution commonly referred to as DPI or dots per inches. Again, most good image editors will allow you to change the resolution of your image. This is probably the best way of reducing the file size and therefore the loading tmes of the page where your image is to be posted, so do try and reduce the file size as much as is possible. If you're not sure, the best way would be to create couple of images with different resolutions and upload them to see what they look like. If you've reduced the resolution too much the image is going to look blurred or wishy washy when showing on the web page. You'll get the hang of it after a few tries., and the community will thank you for the care you've taken in posting your images (lol)
The disadvantages of using Gif over jpeg are that the color pallete is rather small so some image degredation may occur; but for the purposes of web based bowsers it's usually acceptable. Most image editors will have a conversion tool as well as the ability to change the image dimensions, but if you are posting a lot of images it may be a better option than JPEG, which although a lot smaller than BMP is much larger than GIF. A good rule of thumb is if there are lots of primary colors in your image stick with GIF, but if you have a massivley multicolored image JPEG would be the better choice.
You can see my first post using the image facility as an example of what not to post. The first two images are just over 200 x 200, and as you can see are okay, but the next three images are only 100 x 100 (approx) and obviously much too small for a forum image. The last one is much to large at nearly 600 x 800 pixels. I will update this post to add examples directly, but it’s way past my bed time so will do it later today. :) Pity we can’t use emicons yet. There should be an add on to allow the use of them (hopefully)
http://www.giveawayoftheday.com/forums/topic/6132#post-63795
finally you will find many of the image hosting services already add the coding to the links which are [ img ] and [ / img ] (without the spaces), so you don’t always need to use the buttons situated at the top of the dialogue box. Also you can manually type them in when you post links. You may find this easier as I found using the tool buttons caused the links to be placed at the top of my post and meant I had to cut and past them to the correct place.
I’ll add more information and examples of different sizes so that you can see what they look like as well as tidying up my post over the next several days. I’m really busy at the moment.
Regards Whiterabbit