If You Must Be Sick, Be Healthy or How To Scare Your Surgeon

That is, be as healthy as you can muster given your condition.
I'm not going to presume to offer a list of advice. I know nothing except what I have in my own experience, but it was my experience that making myself healthy as possible before my cancer surgery made a huge difference.

One of the first things I did was decide to try smoothies. A Facebook friend's posts made me aware of them and I'd been curious. Having cancer gave me great cause to give them a try.
I was diagnosed on Friday, June 13, and whirred my first smoothie on Sunday, June 15. I decided that carrot, celery, cucumber, garlic and tomato would form the smoothie's base. I based this on assorted Internet sites about cancer fighting foods as well as some personal anecdotes I found online.
I had a smoothie almost every day from June 15 to July 22. I missed one or two days while camping.
I added in sauerkraut, watermelon, other melons, strawberries, blueberries, lettuce, kale, and probably a few other fruits and veggies. Not all at once, but on various days I'd throw in some of these depending on my mood. The base stayed the same.
I felt really good.
I had plenty of energy.
We eat healthy in general here, but this really kicked things up a few levels.

As for exercise, I'd added squats in March. By the time I went into the hospital I was up to 16 each morning. I also do Tibetan Rites and had started bike riding in June. The first thing I noticed when I went for my first ride of the season was how much stronger my legs were from the squats. I used the higher gears I don't normally get to for a few weeks.

On Thursday, the day after my surgery, I was walking alone, often, and for a long way. I went outside a few times. If stretched out the distance from my room to outside and back it would be about two blocks.
I had really good balance, too, despite lack of food and plenty of painkillers.
I credit the squats.
Also, I was accidentally given solid food on Thursday. My surgeon told me that morning he was going to start me on a soft diet, cream soups, porridge, and the like.
Imagine my surprise when I pulled the lid off the noon offering to find roast beef, mashed potatoes, and french style green beans.
I hadn't had solid food since Tuesday. I ate every bite and told my roommate, "It's really good. I must be hungrier than I thought."
This added to my strength and my recovery.

The normal range for a hospital stay after colorectal cancer surgery is 4-10 days. I'd told my friend a few weeks earlier that I thought four days was a bit much and that I intended to be out in three.

On Friday morning the resident who'd assisted in the operation said something about releasing me that day or the next.
I went home Saturday.

When we met with my surgeon earlier this month he said he's been using my stay as an example when he answers patients' questions about the length of  hospital stays after this kind of surgery,
"The usual length is 4-10 days, but I had one patient who was ready to be released after two-and-a half days. She scared me."

How you live your life is your business. How you react to the diagnosis of a serious ailment is entirely your call.
But for me the squats and smoothies are what made my hospital stay as brief as it was, and if I were to offer any advice it is this: If you must be sick, be as healthy as you can be.