So I made this a long time ago, but here's a free printable 20-page comic thumbnail storyboard template for your personal use. What's a comic thumbnail? It's a small, bite-sized draft of what your comic's page will look like. These help to visualize the flow and composition of your story, which in turn can help you figure out the lettering. There's several ways to do this, and this template is just one way to help you out.
There's four versions you can choose from to download: JPG, PNG, CLIP, and PSD. There's even a manga (right-to-left) version of the template, too. No credit is needed, and you can edit it however you want and share it as long as you don't sell it.
Also, here's a few other cool storyboard templates I've used over the years to make my comics: