A ritual for invocation of planetary energies was usually made up according to the particular need at the time and in accordance with common procedures known to the magickian. To invoke the Planets with the Hexagram, you may use the exact same format as the Heptagram Planetary Ritual, substituting Hexagrams in the appropriate places. There weren't normally any particualar points on a star to turn to and open a portal to invoke as in the Heptagram Ritual. The magickian was expected to know where in the sky above him/her the planets were going to be at the time of working. He/She would then turn to those places instead. You may do this as well, or place a large Hexagram on the floor mentally or physically and use that for reference (as in the Heptagram working), or just sit in one spot and make use of the formulae to properly access the link you already have to the planets. Be creative, responsible, and respectful of the entities involved, and you should have little difficulty achieving success. I've included the formulae below for reference; they are nearly identical to those in the Heptagram Ritual. Don't forget to properly banish the planetary energies when finished, but not over or near a talisman you may have charged during the working. The L.R.P. and L.R.H. is commonly used to purify and banish your area before and afterward. For learning how to draw the planetary hexagrams properly, you can consult The Golden Dawn by Israel Regardie (who doesn't have that one in his/her library?). I've been trying to get time to draw some and put them online for the past 5 years, but it hasn't happened yet.