First off, I do not take responsibility for any irrational or unintelligent choices you make while forming or using your realm.
Possibilities: Well the possibilities are basically endless, but assuming you want your realm to be inhabited by humans and animals, you can make all inhabitants have their own minds, so they will be able to make their own choices and have rational thought and other human functions. After practicing, other beings (friends, enemies, spirits, ect.) may be able to enter your realm, but that will be in a later post.
First off, meditate and clear your mind, then move all your pure energy into a ball in front of you, picture the ball forming into the landscape you wish for your world, add the life you want, set evolution in motion, make it begin as a modern planet, make a whole galaxy, or even a universe, or an omniverse, the choice is all up to you.
After your "world" is complete and ready to be entered, picture the energy world solidifying into a physical planet and send it into the universe, but keep a strand or ribbon of energy connecting you and your world, this strand will serve as the trail to enter your world, make the strand enter your world where you want your entry and exit point to be. I suggest putting a generous amount of entry/exit points around your world, for convenience and security purposes.
WARNING: The next step is optional and only should be done if your world is safe or if you can handle yourself.
OPTIONAL: Link your physical body with your astral/spirit body, this is so your physical body will feel what your astral form feels, and your astral body will feel what your physical form feels.
FINAL STEP: ENTRY: To enter your realm, do anything you may do to astral project, and as you are entering the astral realm, have the energy "trail" pull you towards your realm, enter any entry point you wish, and you are in your realm. If done correctly, you will only be able to act according to the laws of your realm, for example, if you made an exact copy of Earth, you as a Human, would not be able to fly, advance time, change into animals, ect. but if your realm allows that, (no gravity/low gravity) then you will be able to do moon jumps of fly freely.
EXIT: To exit your realm, simply go to any entry/exit point and picture your astral body being pulled out of the realm and put into your physical body, the point you leave the realm is the point you return to in the next session.
If you leave the realm without entering the exit point, you will enter your realm-ial (XD) body where you left in your last session, and since time advances at a steady rate, whether you are in the realm or not, your body will be subject to anything that may happen while you are not there (killed, eaten, cut, ect.) so I recommend leaving only by the exit points.
DEATH: If you die in the realm you may feel a sharp pain (if you linked your bodies) near your physical stomach, you will lose anything you are wearing or holding, and will be forced out of astral form and enter physical form again, the next session in the realm will be you needing to pick the original entry/exit point again.
If you have questions or concerns, message me and I will answer as soon as I can.
-Nikita V. Shlarzliya.