the benefits of working in bulk
Working on several designs at a time has many advantages. It means that you can focus on one task to get it done faster, enables you to compare your designs at each stage for consistency, and gives you a good number of WIPs to show your art director instead of three to four finished pieces. I start by getting all my silhouettes working properly, then apply all of the line work, before moving on to colour. I like to colour the whole set at once, so I can keep track of my colour proportions.