As you have not given me more to go on Hans... Here you go

Follow these instructions over the next heap of posts.

1. Open the photo in Lightroom that you want to post to Ausphotography. Once it is open and you have edited it as you wish.
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2. RIGHT-CLICK on the photo, and a menu pops up. On that menu choose EXPORT

The Export Menu
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3. On the export screen, at the top you have to choose where you want to store the edited photo on your computer. In my example I have chosen to put the exported photo onto my desktop
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4. Then scroll down the export screen until you find file settings. Choose filetype JPG and then in the limit filesize to, enter an amount. Ausphotography allows a maximum of 400, so choose something a little under that, say 375 for example. It is up to you, as long as it is under 400.

5. Then in the same section of the EXPORT screen under image sizing, look at the two figures for width and height. Ausphotography allows up to 1200 on the longest side. So adjust these so that the biggest of the two is 1200 (or less).
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6. Then you are ready to export your photo. Click EXPORT at the bottom of the screen.
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Your photo is now saved on your computer, in the right size to upload to Ausphotography. Your photo will be on your computer where you chose to save it in step (3) above.