Create a checklist of things to pack, bring or prepare. Helps to know you definitely packed 3 sets of clothes and have your passport ready.
Keep all your paperwork in a file easily accessible. Try to print stuff if you can because that doesn’t run out of battery.
If you’re the type to fret over prices, have a currency exchange rate ready so you know how much things will cost in your currency. Just a good mental shorthand reference. Have it be what you exchanged it for at the time not whatever the current rate is.