Hi Lisa! It is great that you want to try this!

This is how the video comes across to me. If anyone sees it differently, please say something. I am not an expert on sprouting – I have only done it a couple of times and that was years ago. In the video, she starts first by rinsing the millet really well and putting the clean millet in a spaghetti jar filled with water. She covered it and let it soak for 12 hours. (I guess millet can float and she put a small glass in the container to hold it down.) I do not have a jar like that, so I will be cutting the millet strand into smaller pieces. After 12 hours, she said to remove the millet, and rinse the millet again thoroughly. Let the excess water drip out and shake it gently. She suggests placing it on a rack or in a strainer to remove the excess water. You do not want the sprig getting soaking wet, just damp, to prevent it from growing mold. I am also going to rinse mine in grape seed extract. (heck, yeah!)
So, to answer your question, you only soak the millet sprig that one time for 12 hours. After that, it is just rinsing it off to avoid it from becoming dry. You rinse it off 2-3 times a day. It looks like she just keeps it in a strainer the whole time between rinses. But, I found another video on sprouting a millet strand. This person, after soaking the millet and then drying it off some, wraps the strand in a damp paper towel and puts it in a bottle. So, I do not see why you wouldn’t be able to use your Sprouter. Here is that video if you want to check it out! I hope this helps some. Good luck! Let us know how it turns out!
I found simplified written instructions too!
Step-by-step on HOW TO SPROUT MILLET