Pumping question

laf10

Tomorrow we are going on a 45 minute trip and so far I've just been exclusively breastfeeding. I plan to feed him right before we leave, but he sometimes has to be woken up to eat and sometimes wants to nurse again 30 minutes later. I'm nervous he'll want to eat again soon after leaving slim wondering if I should pump and take a bottle with us in the car. He had to have a couple formula supplements the first couple days and it didn't affect his latch so I'm not really worried about nipple confusion. He'll eventually have to take bottles at daycare anyway, so I will have to be pumping before August. My question is how to start. Do I pump after he finishes eating? Do I need to do it at a certain time of day or more than once to get enough without taking away from what he needs when he nurses. Any advice you can give me to get started would be great!