There is a belief that the negative consequences for a single-manglik marriage can be resolved if the manglik first performs a ceremony called a kumbh vivah, in which the manglik "marries" a banana tree, a peepal tree, or a silver or gold idol of the Hindu God Vishnu.
If Mangal Dosha is present then all combinations which nullify it should be looked into. There are many rules which cancel Mangal Dosha. Drik Panchang considers the most widely accepted rules which cancel Mangal Dosha.
This application provides complete solution in detail.