Click on the image toolbar icon:

The Image Properties panel will pop up:

If you have already uploaded your image to the sever, click on the Browse Server button. The following dialogue will pop up:

Click on the name of the image you want to insert into your page. The name and address of your image will appear in the URL field of the Image Properties panel. Click OK and the image will be inserted into your page at the cursor.

If you want to upload an image to the server, click the Upload tab and the following dialogue will pop up:

Note the restrictions on the image size: 425 kb, width 640 pixels, height 700 pixels.