Have an area:
A comfortable chair, music stand, foot stool, picks, tuner, capo, guitar, guitar stand, pencil, notebook, and your written materials.
Have a plan:
Write down what your trying to accomplish. This is ever changing, but it helps you to stay focused.
Use a metronome, drum machine or backing track:
Everything you practice/play should be in rhythm. Even if it's a very slow tempo, that's OK. Work your way into the desired or "goal" tempo.
Don’t set unrealistic goals. If you can only play/practice for 10 min. do it for 10 min.
But work from a part of your plan so you’re not just noodling.
Practice vs. Entertainment:
Practicing is playing the guitar with intention and purpose. Entertainment is jamming, noodling, scrolling YouTube etc... Both have value but too many students think that entertainment is practicing.
If it seems like you’re having fun, you're probably entertaining yourself!
What to practice
music / guitar theory
chord / scale knowledge
rhythm / technique