Now... You thumbnail.
A thumbnail is a rough sketch. It helps the artist visualize what their final work is going to look like without them putting a whole lot of effort into all the little details. This is the thumbnail of page 34 in Chapter Two of Strawberry Syrup:

As you can see, it ain't exactly a masterpiece. What it IS, however, is a guide to how I want the finished page to look. The panels are laid out, the action is depicted (if roughly), and some of the dialogue bubbles are added in. But why do this step at all?
There are several reasons. The two bigs ones are that it saves time AND your mentail health. With a thumbnail, I can see if the layout works and if everything flows right. If it doesn't, then I've only spent maybe five minutes, tops, on that thumbnail and can just go ahead and take another couple of minutes to hammer out another one, one that will hopefully work. It's way less devastating than spending several hours sketching, inking, and toning a full page, only to find out after stepping back to take a good look at it that something is horribly amiss.
Another benefit is that you can plot out entire chapters of your comic this way in perhaps a day, all before starting your first page. I highly recommend doing this. One of the biggest blocks I run into is getting stuck on layout. By plotting out the entire chapter beforehand, you can see how each page flows into the next, make sure you're not being repetitive in your layout, and know exactly what's coming next. It's all right there, and it can be done in a few days, tops.
So, before you dive head-first into your first page, spend some time thumbnailing your first chapter - you'll be much happier in the long run!
