There is no such concept of bad Shukra. Shukra is the planet which is innately beneficiary planet; it cannot be bad, because of entering in the wrong house, or associated with the wrong planet, it merely becomes weak.
Venus or Shukra is the planet that determines beauty and grace along with finance and earning, and sexual desires. It is believed that if Venus is not in sync with say moon or sun, or if it is in the weak it will not be bad or malefic for other houses as well.
What to do if Shukra is weak?
The following steps can be taken to make the weak Shukra stronger:
It is said that whoever is performing the Shukra Puja, should actually fast from dawn to dusk that day.
Worship Lord Ganesha as he is considered as the Lord of all auspicious beginnings and is worshipped before performing any puja.
Chant the Shukra mantra at least 27000 times in order to get the desired results.
It is advised that you should wear diamond accessories to enhance the benefic effects of Venus.
Pray to Lord Venus on a Friday, if there is no Idol or photo of Lord Venus available with you, you can also pray to Goddess Lakshmi.
Donate white food and Clothing items to women or cows.
Benefits of Shukra Puja and Homam:
The Shukra puja makes the planet stronger, and increases its benefic effects.
The puja enables to maintain peace in the family
When Shukra is strong again it will help in getting the desired boon
Makes your Body, mind and soul pure.