What I should/shouldn't eat to get a perfect shit?

I'm growing tired and angry of having these moist(but still with defined shape) shits. Not only do they cut-off multiple times but they also leave a huge mess to cope with afterwards(after I get it under control I go get a shower). Sometimes I do get a perfect shit - the one that just slides out, leaves no mess, you feel empty after it and could just pull your pants up and leave WC. Thank you for Your suggestions.