from Learn Hindu Astrology Easily, ch. 13
The important principle to remember is that planets give multiple effects. They lift, they cause a fall, they give fortunes and they throw you into the deepest moods of despair. What a planet does is that it gives happiness and grief, rise and fall, and laughter and tears, turn by turn.
It is here (for this reason) that the most important element of astrological prediction comes into play through a very close study of:
1. The strength of planets, which a computer cast horoscope gives.
2. The condition of these planets in the navamsha chart (the 9th division of the horoscope, which again the computer cast horoscope gives. (Does the planet become strenthened or weakened in the navamsha as compared to the natal chart?).
3. Then the dashas, major and sub-periods should be seen.
4. Finally, the transits should be examined, if possible using sarvashtaka varga, which is an extraordinary technique for quantifying the strength of transiting planets.
reprinted with permission