Always read briefs carefully before and after and make a checklist.
Keep to deadlines.
Practice, practice, practice.
Above, three things that can get you through any assignment.
When designing a cover, think about composition. Overlay grids like the Fibonacci spiral on your own art. Or see if it follows the rule of thirds. Looking at rules for photo composition is a good starting point. A cover should always reflect the inside of a book.
See how other publishers design their books by taking a good look at the spine, the backcover, and the elements they contain, e.g. the barcode, the logo, use of imagery, fonts, etc, how it reflects the inside, what colors they’re using.
Picture books usually have the text in black because of selling it to foreign publishers and co-editions. It allows to just print the text on a separate black plate and keep the illustrations.
Becky Chilcott created a list and really good walk-through of useful things to know in Photoshop and InDesign:
• Creating shapes in Photoshop and Indesign
• Using the alignment palette in Photoshop and Indesign
• Changing the colour of an object in Photoshop and Indesign
• Changing the transparency of an object in Photoshop and Indesign
• Using brushes in Photoshop and Indesign
• Cloning images in Photoshop
• Using the eraser and pen tool in Photoshop to cut objects out
• Using the History palette
• Using layer adjustments (like multiply etc) in Photoshop
• Using filters in Photoshop – to use most of these you will need to convert your file to RGB so don’t forget to convert it back to CMYK when you send it to print
• Using the text tool in Photoshop