There are many misconceptions regarding the astrological "rules“...
The influence of the characteristics of the sign in which one is born is more important until the age of 30 – after it is an Ascendant.
Of course, it is wrong. Characteristics of the sign and Ascendant are just beginning of analyzing one's horoscope. When it comes to the Zodiac sign and Ascendant it is important where is the planet-ruler of the sign in which is the Sun and where is the Ascendant ruler (the astrological house and the sign).
A person who does not have any planet in the astrological seventh house of marriage shall not enter into marriage.
This is incorrect because there are many people who are in long marriages, relatively happy without having any planet in the 7th astrological house that represents the astrological house not only of marriage but also of partnerships. An aspect that constitutes the ruler of this house with other planets, especially with Venus, Mars, the Moon and the Sun indicates the relationships in marriage, whether harmonious or not. One of the most difficult aspects is the opposition of the ruler of the astrological house of marriage and the ruler of the horoscope. This is called seesaws aspect in which there is so much love and occasional hostility.
The practice has shown that a reason for the frequent ruptures and impossibility of realization of relationship that leads to marriage is the Uranus in the first astrological house. Uranus is the planet of rebellion, and usually, when it is in the astrological house of personality, a person finds imperfections in each partner or unconsciously chooses those with who have created a dynamic relationship, like a magnet attracts those who will walk away or who will disappoint them.
A person born at the end of a sign has many characteristics of the next one.
This is relatively true. It is proven that people born at the beginning of the sign have more characteristics of that sign, especially if the Mercury (consciousness) is in the sign in which is the Sun. Closer Mercury to the Sun, a person shows more characteristics of the sign. When a person is born in the break between two signs, has characteristics of both and generally is very talented because has the characteristics of planets that are rulers of both signs.
Born in the break between Aries and Taurus 19 - 21 April - are very persistent, charming, passionate, interesting, have the characteristics of someone who is under the influence of the Sun, Mars, Pluto and Venus (erotic charge).
Born between Taurus and Gemini (22 - 23 May), are influenced by the Sun, Mercury, and Venus, and are talkative, witty, youthful, likable, intelligent, capable for business.
Born between Gemini and Cancer (June 21 to 22) under the influence of the Sun, Moon, and Mercury, are very capable for business, noble people who have a lot of friends, they are always at the service of relatives, have parallel sources of income.
Born between Cancer and Leo (July 22 to 23) are those extremes because they are under the influence of the Sun and Moon. Sensitive, romantic, successful, generous, have dominant parents is much attached to them.
Born between Leo and Virgo (22 - 24 August) under the influence of the Sun and Mercury have a sharp perceptive, capable for business, to write, easy to manage in any situation like to travel.
Born between Virgo and Libra (September 22 to 24) are under the influence of the Sun, Mercury, and Venus. They try to keep their cool spirit; they are charming, creative and talented. The success achieves in occupations that require having good reflexes.
Born between Libra and Scorpio (21 - 23 October), are under the influence of the Sun, Venus, and Pluto. Very demanding, somewhat dictatorial, know what they want, exclusive, great friends, and dangerous enemies.
Born between Scorpio and Sagittarius (19 - 22 November) are influenced by the Sun, Mars, Pluto, Jupiter. Grandeur appetites have great ideas, noble, able to earn, megalomaniac, often in conjunction with persons who are on the "edge" of the law; sensual and unfaithful.
Born between Sagittarius and Capricorn (21 - 22 December) are under the influence of the Sun, Jupiter, Neptune, Saturn and Uranus; dictators, good organizers, ambitious, often unrealistic, restrained.
Born between Capricorn and Aquarius (19th - 20th January) are under the influence of the Sun, Saturn, and Uranus; friendly, ambitious, capable, good organizers, unpredictable.
Born between Aquarius and Pisces (18th - 20th February) are under the influence of the Sun, Uranus, Saturn, Neptune, Jupiter; unrealistic, disorganized, chaotic, creative, resourceful.
For a man, it is most important where in his horoscope is Mars, and for women-Venus
This is partly true. Mars as the ruler of Aries and Scorpio and exalted in Capricorn, does not have to give a sex appeal to this signs, but often if placed in these signs can give authoritativeness, rudeness, and violent tendencies. If is in harmonious aspect with the Moon, Venus, and the Sun person manages to express a sexy appeal in a masculine way, and if it is in bad aspects, often makes a person a vengeful dictator.
Women with this position of Mars can be too authoritarian and egotistical because Mars affects in equal measure to both: women and her awareness of herself. It is sufficient that a woman has Mars in one of these positions with a bad set of Venus or the Moon, and that her love life is so chaotic.
If a woman has Venus in Taurus, Cancer or Pisces has more chance of being amorous, but if there is the planet of emotion in Scorpio, Capricorn or Virgo, which makes her a bit calculative or too rational.
If a man has a Venus in some of these signs can be emotionally attached to a woman who is not passionate, emotional but restrained and rational.