$ dockerd-rootless-setuptool.sh install
...
[INFO] Creating CLI context "rootless"
Successfully created context "rootless"

[INFO] Make sure the following environment variables are set (or add them to ~/.bashrc):

export PATH=/usr/local/bin:$PATH
export DOCKER_HOST=unix:///run/user/1001/docker.sock

$ docker context ls
NAME        DESCRIPTION                               DOCKER ENDPOINT                     KUBERNETES ENDPOINT   ORCHESTRATOR
default *   Current DOCKER_HOST based configuration   unix:///var/run/docker.sock                               swarm
rootless    Rootless mode                             unix:///run/user/1001/docker.sock