The following summary is taken out of the publications from the great Dr BV Raman's compilations.
Transiting planets come into conjunction, opposition, shashtashtaka (6th / 8th) position, or trine position with any natal planetary placements, the transiting planets create an energy which indicates some good results and some bad results. There are, however, some basic guidelines to remember when arriving at transit results.
1. Transiting planets, which may be favorable according to general rules, may not give favorable results. This is due to unfavorable placements in relationship to the birth planets regardless of favorable transit position from the birth moon.
2. When Jupiter transits through the exact degrees of a natal planet, it enhances matters in the house owned by that planet. For example, Jupiter, when it passes over the planetary lord of the 5th house, promotes children.
3. Depending on the nature of the planets involved, strong or weak, positive or negative results can be expected when a transiting planet enters into opposition with a natal planet.
4. Positive aspect between the natal and transiting Jupiter indicates positive results.
5. When a transiting planet exerts its influences on a particular sign, the owner of that house also receives the influence of the transiting planet even though it may be in some other house.
6. Whenever adverse results take place, Mars will be transiting the Lagna, the Moon, the Sun, or the houses related to the areas of affliction or it will be in opposition to these houses.
7. When Saturn conjoins or is in opposition to the Sun or the Moon it brings adverse results. Generally, the Moon indicates emotional issues and the Sun indicates government related or official matters.
8. When Rahu & Ketu pass over Saturn, sudden and unexpected developments take place.
9. The Sun’s transit of the Sun sign or opposition to it will bring difficult results.
10. If the Moon transits in favorable aspects to benevolent planets, results will be good.
11. When Dasa / Bhuktis are operating, if such planets in transit are in exaltation, own house, etc., it will give good results, and negative results when such planets go to debilitated signs.
12. A benefic planet becomes more beneficial when it retrogrades. Whereas a malefic planet becomes more malefic when it retrogrades.
13. A benefic planet transiting a benefic house will not give good results if conjunct or powerfully aspected by negative planets. Similarly, negative planets will not be as negative when conjunct or aspected by a benevolent planet.
14. All planets become capable of giving good results when they transit the 11th house provided they are not afflicted by malefic association, combustion, or opposition, etc.