Choose a theme. If you want your CD artwork to be quality, you need to choose a theme and stick with it. If you're a hard rock band and you have decided to use images and artwork that includes stoic photos of your band, make sure you can get someone to shoot them and that you don't stray from your vision. Having continuity will show other people that you are serious and have something to say. Being all over the place with your artwork will come across as unprofessional and lower the quality of your artwork.
Use a graphic design program. Though you may have not gone to school for graphic design, there are many tutorials online for programs such as Adobe Photoshop, Adobe Illustrator and Coral Draw that can aid you in learning one of these programs. Mastering one of these programs will allow you to manipulate images, color and text for your CD artwork. Using one of these programs should not be taken lightly; even if you have someone draw your artwork, you will need to scan the image in to get it into a proper format for printing.
Talk with your printer. More likely than not, you will have an outside company print off your album art. You should ask if they have any available templates and what specifications they have for printing. They will most likely have certain pixel sizes and color settings you will have to follow, so prepare to address those issues. Another option could be to print your CD artwork at Kinko's or the library, but going to a professional printer doesn't cost much more and the job will look much nicer.