The beautiful thing about having a grappling dummy is it allows you to train at any time of the day! If you just got back from the gym and maybe you still have a lot on your mind, bust out the dummy and throw that sucker around a bit! That should help do the trick for you.
Work on your armbars, heel hooks, takedowns or even your ground and pound, you can round out your overall game, or focus on just one aspect.
Pushing The Limits Of Your Game
The training dummy not only allows you to blow off some steam, but it also pits you against your greatest enemy; yourself.
You can actually build a grappling dummy for little money. As little as 30$ is enough to build yourself a grappling dummy.
Judo Olympian and BJJ black belt shows an extremely cheap grappling dummy made from a Gi and towels:
How to build yourself a Grappling dummy in 5 minutes:
Another cheap option:
Sloth Jiu-Jitsu: you can be slow and unathletic and still kick butt in Jiu-Jitsu.