I am the furthest thing from an expert on bonsai styling. But honestly, if you just got your little trees, I would recommend doing nothing. The first thing you need to do is learn how to keep your trees alive and healthy.
You do know that your junipers need to stay out doors year around? They die indoors. Also the soil they are in, looks to be all wrong for bonsai (or really any potted tree). Your soil (as near as I can tell from a photo) looks to be very heavy- possibly even more than regular potting soil, might have at least some topsoil in it.
You don't want to do anything about that now - if you live in any kind of cold winter country, your juniper will be going dormant soon anyway. But the first thing you should do in early spring is re-pot it in to good bonsai soil. https://www.helpfulgardener.com/bonsai/03/soil.html
In the meantime, you can spend the winter reading and learning about bonsai care and styling and studying your tree. Make drawings of it, which will help you find the line you want. Then you will be more ready next year to start cutting. You can ruin your tree for a long time by rushing into cutting, before you have a good sense of what you are doing.
Welcome to the Forum!