Change the bolded values to what ever you like.

[Unit]
Description=AutoSSH tunnel service for SOCKS proxy
After=network.target

[Service]
Environment="AUTOSSH_GATETIME=0"
ExecStart=/usr/bin/autossh -M 0 -o "ServerAliveInterval 30" -o "ServerAliveCountMax 3" -o "ExitOnForwardFailure yes" -C2qTnN -D 8080 USER@REMOTE-HOST
RestartSec=30s
TimeoutSec=60s
Restart=always

[Install]
WantedBy=multi-user.target