Ok here is an easy method that works to summoning demons and spirits. Your going to want to draw the demons sigil on a piece of parchment paper for this ritual. Your going to do this ritual either on a full or no moon. This ritual is the Invocation of Hecate, after invoking her you going to ask her to make the demon you want to conjure to appear for you. Your going to need 3 to 13 black candles an offering, a chalice full of wine, and lots of incense preferable mugwort, wormwood, or patchouly musk. Also you want to dress your candles with conjure oil and carve the name of the demon you wish to summon in all of them. A crystal ball or scrying mirror is optional in this spell.
Surround yourself in a circle of black candles, no less than three (the traditional number is either 13 or any multiple of three).
On the ground, set up your materials, and set all items facing west.
Work this rite any time after dark- during the bewitching hour if possible.
Prepare the atmosphere by casting the incense into the burner and having your sigil visible on the outside of your circle.
Visualize the darkness entering your ritual area, enveloping it in a dark veil.
Surround yourself in the darkness, drink in the night, feel it pulsate within your body.
With every breath, draw more and more night into you, until you are filled with the dark energy.
If at any time you hear an animal- a dog, a raven, or a crows call, then you may move freely into the next part.
If not, invoke spirit Raven into your circle, and ask his blessing on your journey into the abyss.
Next, look upwards to the moon (this should be done outdoors when the moon is full, if possible.)
Let its silvery light shine into your body, going through you like glass. Invoke Hecate, holding your arms into the air saying this or something similar:
You who are the night,
You who are the darkness, the moon above.
Triple goddess, come unto me!
Grand Hecate, I call ye!
Be here oh Queen of Heaven
Unto me oh Queen of Hell!
You who command all things!
You from whom all magic flows!
Great Mystery, oh Shadow of Darkness,
Hecate, I invoke Thee!
You should feel yourself becoming lighter, feel a surge of power, or some tingling, or maybe a feeling of safety, or that you are not alone suddenly. If you experience no change whatsoever, repeat the chant, and if after three times you still feel no change, end the rite and try another time.
When you feel Hecates power, either look at or visualize the sigil of the demon you want to appear and ask her out to cause the demon to appear before you.
If you wish to further channel Her, continue, otherwise give her license to depart.
To continue, hold up the chalice with the wine to the moon and say:
Moon, shining bright above me!
Goddess, let thine blood run down! Feed me with thine darkness!
Make me thine Kindred!
Drink the wine, and continue to channel the Goddess until you are satisfied.
The demon should appear, it can manifest within the smoke of the incense, within the flame of your candle, or if you decided to scry, it should appear in your crystal ball or black mirror. After your done politely ask Hecate and the demon to leave. Afterwards you might want to smudge your ritual space.