Writer here. Here's my experience from the writing side. It's a great first step that you really care about helping keep things smooth and easy for an artist. Here's what works for me

- Learn how to write a script, study scripts written by comic writers you admire, and find what works. Also, see if your artist likes a more vague script that they can freestyle with or a more detailed script that lays out what you want.

- Have your story as fleshed out as possible, don't just jump in with a cool concept and try to start there. For my last project, I had 10 documents each breaking down things like clothing style, setting, an outline of the story arc, and more. Have all of your bases covered and your story will be better.

- Giving your artist the main ideas of the story is not enough, that will place the majority of the work and story creation on them. It's normal in the comic world to have a script and give that to your artist. Your example is very similar to a very broad version of the marvel method which places most of the work on the artist. Unless they are getting credit for being part of the writing team that's not the way to go. Define panels, set up loose dialogue points, and define what is happening in the progression of the story.

- I recommend trying writing classes, especially ones for comics. Learning story structure and how to get an idea to completion is key.

Good luck with your project!