When starting a session, its never a bad idea to be a bit over-prepared. Overcoming minor roadblocks and hitches, especially early on, will get things off to a good start. The following items have come in extremely handy for me numerous times (particularly when working at a studio that is unfamiliar).
1. Harddrive – Kind of obvious, but having a reliable backup drive is crucial. My professor in college always told us in regards to the digital domain “If it doesn’t exist in two places, it doesn’t exist at all”. Taken with a grain of salt, but you never know when the session drive is going to crap out or files get misplaced etc. Also comes in handy if you are mixing a project from home or working in different locations.
2. Pencil and Paper – Keeping good notes will help you out in the long run. Many artists will spout out ideas and have no idea what they said an hour later, so its good to have a reference to come back to. Jotting down mixing ideas, documenting external device settings, or just listing potential overdubs is stuff to stay on top of.
3. Headphones – any respectable studio will have decent headphones. However, its convenient to have an extra pair you are familiar with. This will be an advantage when you are doing critical EQing, auditioning microphones, or simply getting the headphone mix together for the band.
4. Drum Key – These are extremely easy to misplace. Instead of spending a half hour looking for it in the studio equipment room, keep one in your bag.
5. Guitar related items – Although technically the respobsibility of the performers, it is good to have extras. Tuner (with batteries), spare set of strings, 9v adapter and picks. Simple things like this can stall a session out of nowhere, so being able to replace them on the fly can save the day.
6. Flashlight – Comes in very useful when placing mics on guitar cabinets or crawling around behind consoles and outboard gear racks.
7. Blank CDs/DVDs – At the end of the session give the artist a rough mix of the days work.
Bonus – Laptop – This is not as important as the others, but can also come in handy. Possible uses are playing back mixes, auditioning sounds, and finding out where to eat lunch.