You can use paper to make character sheets, make and use monster stats,
remember initiative, draw maps, plan sessions, and more.
Pencils would be used to create everything above,
to track health, and to doodle in spare time.
Dice are used, or rather rolled, to attack,
make ability checks and saving throws, and more.
Creativity can be used to create pretty much everything in the campaign,
from the story to the characters themselves.
Extra items are useful, such as The Dungeon Masters Guide,
The Monster Manual, and The Player's Handbook.
Character sheets that set a general guideline are also helpful,
and a screen Dungeon Master is always useful when concealing plans for future sessions.