drier and driest
Dry, drier, driest. Adjective, comparative adjective, superlative adjective.
drier, driest
Dry, drier, driest.
"Dried" is the past and past participle of dry. As an adjective, the comparative and superlative forms of dry are drier and driest respectively.
There is nothing wrong with the comparative drier, but native speakers frequently use "more + adjective" instead of the comparatives. Sometimes a comparative will just sound strange to a speaker, who then replaces it with the "more + adjective" phrase. I use drier and driest without any hesitation.
drier
Sleep is a noun and does not have a superlative. Sleepy is an adjective and the superlative is "sleepiest."
The superlative for willing would be "most willing." There is no one-word superlative.
"Studying" is not a superlative, as it is not an adjective. "Most studious" is a superlative of "studious."
"Bib" is a noun and, as such, does not have a superlative form.
Trash it.