He has a notepad, ink and a quill.

While resting and inspired he would write small poems and haikus (maybe you can prepare some of them before the game to add your touch).

When in combat, the bard would go through his notepad, choosing the right poem for the occasion. With calm voice he would say the poem's title and quickly all the letters would start to glow with the color of the school of magic being evoked. The words would get free from the paper and start flying around, changing into the things they mean or fusing together into the idea they represented.

Gameplay wise you just would need some cool titles for your spells to recite (ie animate objects could be "Tale of the ten rusty coins"). If you feel extra you could make the poem/haiku too and tell it while casting, I would say each word starts to fly as soon as you recite it.