Because we are spiritist, we view a lot of spiritual phenomenon as being a result of a spirits acting.
Spirits can assist astral projection into lucidity in a dream. Astral projection actually is not lucidity, it is more from an awake to projected trance state, but some interlapping can happen. For example as the astral dream land is a layer above the etheric and earth, from there you can also project into or visit other higher realms. Ask them when you pray or talk to them to come into your dreams. Ask them to help you in your dreams, to teach you specific things.
For example I had two different experiences one was more like a dream "possession", where I merged into a deity. We were both riding horses, mine was black hers white. She was infront of me, but instead of colliding we merged. Before this her and another deity were around me holding hands half running in a circle. This was before I found my afro-spiritist path. From there we went to a completely different place. I was concious of the events and able to act, but felt different around myself.
The second example I was semi lucid dreaming. My father Lwa Papa Candelo was behind me and as he moved his arms over mine, my arms would move involuntarily. He was having me prepare a spiritual object. Then he started pulling me out of my dream and physical body. It was a failed attempt because the energy influx and movement was too great and fast that I got anxious and stopped the spiritual assistance by fighting it.
By working with our spirits when we are awake it builds relationship, then they will communicate with us on the dreamscape. We will have an increased sense of importance and receive teachings and knowledge. By working with and empowering our ancestors when awake, those from hundreds or thousands of years ago will make their prescence known, and a major way the spirits connect is in the dream time. I often find myself in a classroom or garden for this purpose.
There is a way to "dream true". We put a clear water glass beside the bed to filter incoming to our conciousness. This is replaced new each day of continued effort and not to be drank. Some practice by taking at least a shower before bed, or with a spiritual bath to refresh their head and purify for a clearer spiritual connection: Light, clear, clean. When we lay down we can picture ourselves standing on the earth and growing huge larger than a giant, our feet still on earth but we can see the planet below with a white light overhead we are rising to. See this white orb shoot a beam into your head, through your body into and through the earth into infinity at both ends. This helps to expand your awareness and astral body, as well as clear your channel. Some people also keep a glass of water under the bed or in the corner of the room with a small block of camphor in it to keep negativity away.
Which brings me to intent. We need to say I will remember my dreams on waking, which announces our will.
Secondly we have Allan Kardec's book of prayers, prayer for reunion upon sleep. This invites good spirits and guides to come meet with you there. It also asks them to protect you on your dream journey. How to protect yourself in the dream realm is another blogpost for another day however.
My soul is about to meet for an instance with the other spirits. May the good ones come to help me with their counsel. Guardian Angel, may I upon awakening preserve from that event a healthy and lasting impression. Permit my spirit, oh God, to meet with my loved ones who have departed, and may I receive from them spiritual fortitude and good advice. Amen