How do I pray for my deceased mother so that she may enter Jannah?

Allah Almighty commanded kindness to parents and praying for them. Kindness to them after their death includes seeking forgiveness for them, paying off their debts (whether they are a right of Allah or a right of people), and giving charity on their behalf. The Prophet, peace and blessings be upon him, was asked about giving charity on behalf of the deceased, and he permitted it. In fact, he clarified that providing water is among the best forms of charity.