Got to
www.tinypic.com Dayvo.
Click on the resize button and select the size indicated for 'messageboards' etc etc...
Click on the 'Browse' buton and you will see your computer files/folders and what have you...look for the folder that contains the image you want to upload.
Double click on it to add that location into the space you can see just to the left of the 'Browse' button...
Click on UPLOAD - the green button underneath.
When the upload to tinypic is complete, there will be a line of code "for messageboards/forums" etc.
Highlight this line of code, press Control C, go to the reply box where you are composing your message, click to get the cursor blinking in the box and press Control V.
The line of code should appear.
Click on preview post - et voila! (Not so famous last words..)
Just an echo of Barq's useful notes really, but - if I can do it - you can do it!