I’d suggest watching these short clips that @J805 created for Responsive Design. Although short, they were enough for me to understand how Bubble interprets responsive settings. E.x. spacing, alignment, etc. To be honest, it’s a ton of trial and error. What I did, was create my app, then clone it and just named it (App 2 Sandbox) or something. That way I could play around with a copied version of my application without messing up the one i’ve worked hard on.
Feel free to reach out if you need help.