I thought universalism means one believes everyone will be saved at last. Evangelism is how we work alongside God to bring about that kingdom where there is enough of everything, including salvation, for all.

That is correct. Even if one believes all will be saved at the last, one can also hold that the most fulfilling and God glorifying life is one lived for Christ, being his hands and feet, sharing God’s love by cultivating his Kingdom here on Earth by seeking peace and justice for all.