General background, written plainly. None of it is a substitute for your vet.
What to expect day by day when a cat first comes home, and why hiding under the bed for five days is normal.
Cats evolved in deserts and have a weak thirst drive. Here is roughly how much they need and why it is hard to tell whether they are getting it.
The carrier is usually not the problem. Here is what actually makes vet trips hard and the parts you can change.