There are 4 tricks to making good clouds with a Nautilus.
1. Use 40PG/60VG ratio juice.
2. Remove the airflow control ring. It's pretty easy to remove and doing so exposes all 4 airholes plus a 5th hole where a spring is inserted all at once. It provides similar airflow to the Kanger Subtank on the middle setting. (Lots of youtube videos showing you how)
3. Run the tank at 13-15 watts.
4. Take straight lung hits.
You won't be winning any cloud blowing competitions with it, but....
It works.