This is a folk magical way, strongly influenced by hoodoo traditions. It lacks the fireworks that a traditional ceremonial evocation (done correctly) can provide. Still, it’s a good way to do it if you don’t want to expend a lot of energy and only need information / conversation.
Draw the sigil of the spirit on a small piece of paper. This is important. It makes a much stronger connection than printing it out or just looking at it in a book / online. If there is no sigil available, you need to be able to address the entity. So title it, “The Spirit in My House” or “The Spirit Disturbing My Cousin” or whatever describes how you are aware of it. Then write its name / title, cross out repeated letters, and make a sigil with the remains.
Put the sigil beneath a full glass or bowl of water. Make sure these are transparent and made of glass or crystal. No plastic or opaque materials.
Burn incense. For air-oriented spirits, pure frankincense is very good. For spirits of the dead, try wormwood and / or pure myrrh. For all others, a balanced blend of frankincense and myrrh is excellent. I have found Champa is also generally useful for all spiritual operations. Avoid dragon’s blood and dogwood. These disperse spirits in this tradition. With the exception of these two, any incense is usually good incense to burn. Far better to burn some than not.
Make your chamber dark and chant / vibrate the spirit’s name over the water until you feel its presence. This shouldn’t take long if you’ve done the work up to this point. If you used a title instead of its name, look back at the scratch paper where you crossed out the repeating letters. The remaining letters you used to make its sigil might look something like this (if you were using “The Spirit in My House”): “Sprnmyou.” Say that a few times until it sounds like a word of evocation. When I do it, it sounds like “Spare-nim-you.” I would then take that as a mantra of calling to chant if I didn’t have the spirit’s name.
When the spirit arrives, ask it what you need to ask. It might appear before your eyes over or in the water (like in a scrying crystal or black mirror). It might appear somewhere in the chamber or in your mind’s eye. You might hear it or just get mental images or a stream of unique ideas that respond to your questions.
When you’re finished and everything has been said, bid it politely to depart: “Go in peace, harming none, and let there always be good relations between us.” It will nearly always go. If it doesn’t and you realize you have a particularly ornrey spirit on your hands, have a piece of solid camphor (you can buy it in blocks) or camphor oil ready. Tell it to go three times and then put the camphor in the water, ventilate the chamber (making sure the incense is no longer smoking), and toss some blessed salt in the corners of the rooms. That should take care of any lingering.