For a long time I tried to find out if out-of-body experiences are influenced by environmental factors, such as weather, moon cycles, biorhythms, etc. I usually kept good records of my OBEs so that I could study these variables. Here is what I found:
Weather
Weather doesn't seem to influence my ability to have OBEs. I've lived in Arizona as well as Minnesota, and I've induced OBEs when outside temperatures were near -30F and also when outside temperatures were near +115F. However, if my body is too hot or cold, it's hard for me to achieve the focus needed to induce an OBE. It doesn't seem to matter if it's raining, snowing or sunny.
Moon Cycles
Some people believe that the moon can affect our ability to induce OBEs, but I think that's a myth. I studied the moon cycles a long time and found no influence. I've had OBEs under full moons, new moons, and everything between. For one period of study that spanned over a year and a half, I averaged a 58% full moon.
Biorhythms
For a long time I kept track of my biorhythms, in the hopes that I would find a correlation. Biorhythms didn't seem to make a difference. I've had OBEs on Physical, Emotional, and Intellectual "critical" days. I've also had OBEs when these influences were farthest from their "critical" period.
Months of the Year
I've had OBEs in all months of the year. Strangely, I usually have fewer OBEs in July. I suspect that's because July is when I have the least amount of time to practice.
Days of the Week
I've had OBEs on every day of the week, but I've had many more OBEs on Saturdays and Sundays. That is because I have the time to practice then. On the weekend, I can stay in bed late and induce OBEs once my body is fully rested and relaxed. During the week, I don't normally have the time required to induce OBEs.
Special Days
Halloween is traditionally considered a special day, the day that spirits can influence and communicate with the physical world. Other days such as Christmas, Easter and Thanksgiving have special meanings for various groups of people. These special days can evoke feelings in believers; fear on Halloween, peace on Christmas, worship on Easter. Do the collective feelings of these people affect our ability to leave the body? As far as I can tell, no. What about the emotions we have on these days? To some degree, I believe our emotions do have an effect. Once, I was uncomfortable about leaving my body on Halloween because I thought it would be a perfect opportunity for spirits to possess my body. But I did it anyway, and there were no complications.
Prior Amount of Sleep
I've had OBEs with various amounts of sleep. I recommend getting lots of sleep before you try to have OBEs. One of the biggest problems is trying to induce OBEs when the body is too tired.
Prior Music Listening Habits
Music relaxes my consciousness too quickly to induce an OBE. During practice, I like to hold on to the edge of consciousness as long as I can. If I listen to music, I get distracted by it and drop off quickly to sleep. Therefore, I recommend silence.
Food
As far as I can tell, food has absolutely no influence on my ability to have OBEs. However, people have reported that fasting can increase the ability to have OBEs. I've never tried fasting. Some people believe that vegetarianism is better for OBEs. I've tried a vegetarian diet (except for eating dairy products) and it didn't seem to make a difference.
Liquids
I haven't found any correlation between my intake of liquids and my ability to have OBEs. I do recommend avoiding alcoholic beverages before trying to induce OBEs. Alcohol unfocuses your mind. Believe me: You need as much focus as possible. Sylvan Muldoon recommended jarring your subconscious into taking you out of body by making yourself as thirsty as possible. Muldoon claimed that if you went to bed very thirsty, your subconscious will sometimes "sleepwalk" astrally toward a source of water. In other words, your subconscious detects the thirst, and tries to satisfy it subconsciously because you refuse to do it consciously. I've never tried this method.
Reading
Reading OBE books does influence my ability to have OBEs. When I read a book about OBEs, I focus my full attention on the topic while I'm reading, and that sends a message to my subconscious: Let me out! And it does.
Direction
In Journeys Out of the Body, Robert Monroe recommended pointing your body North when trying to induce OBEs. I've tried to have OBEs facing all directions, and I've been successful in all directions. Strangely enough, I have my best luck when my body is pointing West. I have my worst luck when my body is pointing North. When I induced the vibrations the first time, my body was pointing West. Perhaps it's more effective to point the direction you did during your first successful experience.
Practise
By far, the biggest influence on my ability to have OBEs has been the amount of time I spend practicing it.
Exercise 23 - A High-Pitched Whining
During your OBE practice sessions, you may have noticed a high-pitched whining noise in your head. If you listen closely, you will notice the noise I'm referring to. We all hear this high- pitched sound constantly, but normally the sound is drowned out by constant distractions and sounds all around us. Most people don't notice it, but some people have a disorder called tinnitis, which causes this sound to be unusually loud and distracting. You can use this sound to induce OBEs.
For this exercise, relax and focus your mind as before. Then start listening for this whining sound in your head. Once you find it, use your imagination to try to increase the pitch and volume. Increase the pitch until the sound is almost out of the range of your hearing. This can cause the vibrations to sweep in and free you from your body.
Personally, I think the sound has nothing to do with the vibrations. This exercise is effective only because it can teach you how to properly focus your mind.