It's something that takes time and practice. In general:
Keep a regular sleep schedule.
Avoid caffeine after or near 12:00 PM
Do not lounge in bed. Teach your body to associate the bed with sleep by only laying in bed when tired. If you do not fall asleep, get up and do something else before trying again.
Diet and exercise.
Practicing deep relaxation and meditation can help recall dreams.
Using affirmations before sleep such as "I will remember my dream" or "I will dream of ______" may also help.
Keep a dream journal. Document anything you remember. This will help associate the dreams with something valuable for remembering.
I think it'd be best however to limit the incubation process to spirits (such as the deceased, deities, or other spirits you work with) and other dream working functions. I do not know how fortuitous it will be attempting to connect with another person through dreams. It may be a better idea to shoot them a message, write a letter, or call them.