This is a basic in magick - on this site we call it having good spiritual hygiene. Doing baneful magick attracts baneful entities - LIKE attracts LIKE - is a tennet that hold true most of the time.
You need to know how to keep you and your space clean. You clean a kitchen before you cook so you don’t get sick from germs, you shower to stay clean and healthy, so must you also keep your energy clean of astral parasites and usurious beings.
The first thing to get under your belt are your protections: se the spiritual hygiene collection, then you want to get into developing your astral senses and avoiding impostors and parasites.
Do not evoke or invoke until you can know you’re clean and not talking to lesser beings.