The words of the hadith "His deeds come to an end" mean that he/she is not able to perform good / bad deeds any more and thus can not receive rewards anymore. But there are three kind of deeds for which he / she can receive rewards after passing away. 1. Sadaqah Jariyah: Any good deeds done by a Muslim which benefit the people even after death of the person who originated it. For example, the establishment of a free hospital, orphanage, welfare trus, educational institute etc. from which the people benefit will be sadaqah jariya for the person who established it. Some other examples can be planting a tree, providing water on a public place etc.
2. “knowledge which is beneficial” means knowledge which benefits people become better Muslims. As long as people benefit from his knowledge, the teacher will get rewards for it. This is very powerful way of multiplying your rewards. Just imagine of an Islamic teacher or any person who keeps sharing his knowledge with the people around him / her. And the people act according to his knowledge. The person who shared the knowledge gets rewards for all the people who performed good deeds because of the knowledge shared by you.
3. "Having virtuous descendants" If you give good Islamic education to your children, they will definitely keep making duas for you after your death. And if you train your children to perform certain good deeds and they keep performing them after your death, definitely you get rewards for all the good deeds they perform as you are the on who guided them on the right path.
Here we share a dua that you can make for your loved ones (with meaning and voice)