Just use a phiomia with a lot of stimberries.

1 Tame a phiomia with bolas and a club

2 Build a structure of your choice to house the phiomia and collect poop

3 Gather tons of stimberries (I use a moschops)

4 level up the phiomias food only. Dont waste points on other stuff your never going to use it for travel.

5 SHOVE THE STIMBERRIES DOWN ITS THROAT AND GIVE IT DIARRHEA LIKE YOU AFTER HAVING TACO BELL

6 You now have a lot of poop. Just dont tell PETA what you did. :)