This is a great question, and one that goes perfectly with the challenge theme- thank you for sharing it, @chaitea43! 
When it comes to staying safe in the practice, I often hear that if you are practicing and casting with good intentions, you do not need to fear attracting evil- some might say that “you get what you put out into the Universe”. However, this advice is largely for when we are casting for ourselves within our own bubble of influence- when we are working with outside forces, I personally think it’s a good idea to consider other methods of protection! 
I would group protective methods into two main categories:
- Protection in the physical plane (aka where your body is)
→ For protection in the physical plane, the foundational Protection Magick is my recommended go-to: everything from Protection Spells to herbs with protective properties, lighting candles with protective colors, to drawing a protective circle, etc.
- Protection in the spiritual/otherworldly plane (where your mind/spirit/energy is traveling to)
→ Depending on where you go, the Laws of Physics may no longer apply. Protective methods can thus vary significantly- you might try to look for protective items you recognize and use those, or you might try casting protective spells or items that will go on the journey with you (like a protective travel bag).
- Lucid Dreaming - As for Lucid Dreaming, if the dreamer is able to gain a lucid state then they have nothing to fear as they gain full control of the dream space. Any entities can be summoned at their will and be controlled as they please. Protective methods aren’t needed here, in my opinion, but could also be summoned and used as the lucid dreamer pleases.
These are just my personal thoughts and practices on protective magick- it really is cornerstone of the practice, in this and in any world! 
I hope these thoughts can help you, and I imagine others will likely have some other thoughts and input for you too!
Blessed be! 