What do we need to know to effectively read a horoscope?
1) We need to memorize and understand what each house and sign represents.
2) We need to memorize and understand what each planet represents.
3) We need to understand planetary dignity and how it effects the different areas of the chart.
A planet in good dignity will help the house that it is placed in. If it is Jupiter, then the person will have good opportunities in the area represented by that house. If it is Saturn, the person will have tenacity and the ability to endure all challenges in that area of life. If the planet is in bad dignity, it will hurt the area of life represented by that house. How will it hurt it? That depends on the innate nature of the planet in question. Mars will cause injury, and sudden change. Saturn will cause delays and hardship. Jupiter will cause us to be too optimistic. Mercury will get us lost in the details and ruin our ability to manage that house.
If we can start with this basic knowledge we are on the right road to reading a horoscope.
The following video explores this idea of planetary dignity in detail.