Meli,
My stomach got butterflies knowing what you're about to go through. I'm 10 weeks post Tx but the memories of treatment are still very fresh.
As Christine said, hydration and nourishment are vital but I found it was a lot easier said than done. I was unable to eat the last two weeks and I ended up with a PEG two hours after ringing the bell. The 2-4 weeks after treatment are equally as rough as you will continue to "cook" for a while after treatments are done.
Staying ahead of the nausea and pain is key. Make sure you take your meds prior to the symptoms hitting you. It's a lot easier to keep pain away than it is to make it go away. The same with nausea.
Communicate all your symptoms to your team. They don't know if you don't tell them.
I won't pull any punches...Treatment is brutal but you'll get through it.
Heed the advice of the folks here and do what you can to follow it.
Positive thoughts and prayers
"T"