What I've learned in illustration Tip#1:
Sometimes I find that I have a great idea for an illustration. Maybe its a great character with the perfect gesture or an unusual object that would be perfect for the message I want to convey. But as I start sketching, I find that I get wrapped up in the scene behind the focal point portion of the illustration instead. Its like I keep putting off the best part; the punch line so to speak. Something in the back of my mind wants to save the best for last, to build up the scene around it just right and make sure everything's in place and planned out perfectly before drawing in the most important part.
I've learned to stop doing this.
For me, building up an image with the focal point first allows everything else to fall into place naturally…almost magically. When I try to plan the scene first, the drawing becomes forced, less powerful, and the focus gets lost and the message watered down. In the past, I studied single panel cartoons, and noted that this type of art delivers its message very quickly, within a few seconds of viewing the image. Everything about the image must deliver its message clearly without any distractions taking the form of extraneous or oddly placed background material, or out-of-character... character details. Cartooning lessons could be applied to any artistic discipline. Sometimes our great ideas get lost when we over think it and smother them out with our over planning. If you have an exciting bit of inspiration, don't beat around the illustration bush.