Normally, I would just play the selected song and then repeat a small section of the music memorized and then after doing all of the measures I would put them together. I play Tuba in the marching band but the school only has four tubas and two of them had to go to the shop which left two that the upper classmen got to before I asked my band director for one. Now I have to memorize the show music for next year in the next two months and I'm a auditory learner so I need a little help? I recently switched to Bassoon to practice at home so I was wondering if you don't have any tips will it suffice to play on the Bassoon until I can find a tuba to play.

I think you need to develop the "muscle memory" of the fingerings as well as consciously memorising the notes and the sound. Bassoon isn't going to help with the fingering. Is there another pitch of valved brass instrument in the same key you could borrow to practise on? What is in the same key as the tuba but an octave up? That could be played with the same fingering couldn't it? Or even practise a transposed version - unless you have perfect pitch. I'm only slightly familiar with brass so may be talking rubbish. Try asking on viva brass.