Install a Dark Souls - Official Map modpack server through the Control Panel (Servers → Select your server → Game servers → Add Game Server → Dark Souls - Official Map modpack)
The setup was easy as it can be. I first got scared that automatic mod pack installation will take an hour as someone has to do it from the staff, but appears it is being done automatically and I got my SkyFactory 4 server ready to play in 5-10 minutes. Highly recommend.