Anyone who had a firsthand experience on how to have a stress-free air travel with a toddler? Please share some tips.

I've travelled with my turning 4yr old daughter for 4 times in a plane. Though they were just short trips, like 1-2 hours only. She has her own luggage full of toys and food. I let her play and run around the airport or play at the designated playground (if there is one) so by the time we get to the plane, she's tired and would prefer to go to sleep or eat or latch on me since we are exclusively breastfeeding. Bring the toy/book that your kid really likes to play/read with so she/he will be occupied. Get your child active before the flight so by the time you get to the plane, she/he got less energy to move around. Hope I helped.