So lately, As I've been working with my miniatures, I notice that they are always getting in my space, and pushing me around, I'm not okay with that. As it can lead to many other problems and it is dangerous, no matter how small they are. How do I train them about space bubbles?

No one wants to be hard on cute lil mini pons. ❤️ Because of that they often get pushy. But as you said that's only the beginning of many problems, so it must be nipped in the bud. No hand feeding, no letting them scratch on you, and when they attempt to get in your space take a lead rope and crack them on the nose. I know a lot of people don't want to do that, but it won't take long for them to realize if they stay where they belong they've got a good life. Both you and mini pons will feel much more comfortable.

My OTTB Roman is far from a mini XD but when he gets in my space, he gets an elbow (probably won't work for a mini LOL), cracked with the leadline or instantly stopped and backed up. Lots of repetition.

Thank you guys! Sometimes it can be hard to remember who is boss, and they often need a reminder because they are so cute <.>

We have a 3 yr old who loves to get in my space and when he does, he either gets whopped in the chest with a hidden broken, purple crop or I stop him so he has to pay attention and then back him up to make him think about something other than creating a bloody hole in my arm. (He isn't mean, that is just his way of saying, "I LOVE you human! Play with me more!" He often forgets that he is tougher than me.....

Yes, definitely!

Google Warwick Schiller, his training program has completely changed my relationship with my horse for the better!