First thing is to have a host. There are 2 that I know of and they are www.hunt101.com
I use photo bucket as in my opinion it's easier to use.
Click on the link to their homepage and if you have not made an account you will click on "sign up free" to get an account. If you've already signed up for an account in the upper right corner click "login". Once you have done this you type in your user name and password. Then click sign in or hit your enter button. This will take you to a page that will allow you to upload your pictures to the account. You will see a browse button.
Click browse and another box will open that allows you to browse to the part of your computer where you've saved your image. Once you find it you click on the image and click ok. Then click submit (found underneath the browse text box). This will take a copy of your picture and put it up on the net in your account. Once finished you will be able to see your image underneath the upload box. It will have 3 buttons (move, edit and delete) above the images. Then you'll see the image. Underneath you will also see 3 elongated rectangular boxes. They are labeled url, tag, and Img.
To post a picture here you can copy/paste the last line (IMG).
To copy paste your linkfrom photo bucket, you will use the URL line. Place cursor at beginning of the line and hold down your left mouse button and while holding it down slide your mouse to the right so that you turn the whole line blue (the text will turn white). Once this is done, make sure your cursor is on the blue part, right click and select COPY. Then when you are here, and have clicked the image box and removed the URL, you right click again and this time select PASTE. This will make your link show up between the 2 sets of tags. Upon viewing your message you will not see the brackets with the tags. They become invisible, however they tell the browser to link to the image stored at the address you inserted between the tags.
If you don't think you can do that, then there is still one more option. On photo bucket, you can select the IMG option. You copy/paste the same way as instructed above, only you don't have to worry about clicking the image button here as the code is already part of what you have copy/pasted. So all you do is type your message then underneath that, right click and select paste. Upon posting your message you will have an image showing up.