First, you need to have a Photobucket account and you need to be able to upload pictures to it. If you would like to know more about that, let me know and I will add that later.
After you upload a picture, you will need to resize it. If its too big, only part of the picture will show in your post.
Click "Edit" on the menu bar at the top of the page, then click on the picture that you want to edit. Next, click "Resize from the menu above the picture.
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Select 800 width. If the lock in the box between width and height is locked, the height will automatically adjust to match the width.
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Click "Apply". On the next screen, there will be a box that you can tick if you want to replace the original pic with the resized one. If you don't, you will have the same picture in two different sizes in your library. Don't forget to click "Save".
In the drop down menu under Image Links, click on the box next to IMG code.
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The box will turn yellow for a second and the word " copied" will appear in it.
Next, open a new tab in your browser and go to the Fordson Tractor Pages bulletin board. Start a new topic or reply to a post, like you normally would. When you get to the place that you want your picture to appear, right click with your mouse, then click "paste".
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The code that you copied will appear next to the blinking cursor and that's where your picture will be in your post.
That's all there is to it. It gets easier after you do it a few times.