When you convert a Word Document into an .rtf file with pictures, (Or simply save an .rtf file with pictures) the file size can be dramatically increased. This means you can't upload the .rtf document into Springboard.
The following is a quick method that should reduce the size of the the document.
1. If the original file is a Word document, make sure the original file is in a 97-2003 Word Doc (.doc) format; it doesn't always work with later (.docx) versions.
2. Click on one of the pictures.
3. Click on Picture format from menu as pointed in the screenshot below
3. Click on 'Compress Pictures'
4. Select 'Apply to all Pictures in Document.'
5. You can try different settings, however web/screen usually works well for 'Change resolution.'
5. Un-tick 'Compress Pictures,' this will compress the images twice, resulting in low quality images.
6. Go to File/Save As.. and save file as .rtf.