Planetary hours are divided into two parts:
Sunrise to Sunset
Sunset to Sunrise
Each hour of the day is matched to a planetary influence. Because only the sun and six planets are used as correspondences, you have a chance to use those influences either during the day or during the evening. The influences can either help or dissolve our magickal efforts. Planetary hours are calculated with reference to the rising sun, so each time you wish to use a planetary hour, you must first know precisely when the sun rises where you are living. Here is how you find out the planetary hour. Follow the directions below (which takes too much time to do) or just go here. It's easier. :)
1. Find out out time the sun rises in your locality. This is not difficult. Use the Weather Channel on television, check the daily newspaper, or look in an almanac.
2. Check the sunrise/sunset planetary hour charts provided on this site.
3. Check the type of working that you wish to do, and consider which planetary influence is best suited for your work. Write it down.
4. Choose which chart to use. Do you prefer working during the day or after sunset? On the chart, find the appropriate day you wish to use. If it is an emergency, you can do the working today. You don't have to wait.
5. Divide the number of minutes of daylight by twelve. For example, if the sun rises at 7:00 a.m. and sets at 4:00 p.m., you would divide the nine hours of daylight by twelve to calculate when the hours fall. That means that although we call them "planetary hours", the planetary hours will equal more or less than the normal sixty minutes we associate with one hour. In this example, the nine hours of daylight equals 540 minutes; 540 divided by twelve means each hour equals forty-five minutes. Therefore, Hour 1 would be from 7:00 a.m. to 7:45 a.m. Hour 2 would be from 7:45 a.m. to 8:30 a.m., and so on until sunset.
6. In Step 3, you wrote down the planetary influence you needed for the working. Find that planet under the day you choose in the chart. Run your finger over to the hour column; what hour does it fall under? In Step 5, you determined when the hours fell today, by using the sunrise (or sunset) of the day. What does the planetary hour you choose in the first column equate to today? This is the most auspicious time for you to do your working.
Let's say the first time chosen is impossible for you. You'll be at work. Go back to the chart to the correct day, and look for that planetary influence again. Run your finger back to the hour column, and calculate in today's time. Is it better? No? Let's take this example further. If you can't perform magick during the daylight hours, you will probably prefer to take your time and plan the working at night. Use the chart for the sunset planetary hours. Say that the sunset is at 4:00 p.m. and the sun rises the next morning at 7:00 a.m. The planetary hour calculations you did for the daylight hours would not be accurate here, since you have fifteen hours of darkness (as opposed to nine hours of daylight). Fifteen hours equals 900 minutes, which means that each hour equals seventy-five minutes (900 divided by twelve). Therefore, Hour 1 would be from 4:00 p.m. to 5:15 p.m., Hour 2 would be from 5:15 p.m. to 6:30 p.m., and so on. Finally, if none of these hours will work for you, either wait until the next available correct day and time or find another planetary influence that is close to what you need. Why all the fuss and bother, anyway? Calculating planetary influences puts you one step closer to a successful working, especially if other things can't, don't, or won't fall into line for you. It adds extra punch to the minor magicks and could give you success if you are feeling under the weather but must perform anyway. The hours are excellent for planning rituals as well.