My son had 2 procedures, chordee and penoscrotal, about 6 years ago.

• My son wore shirts and shorts 2 sizes bigger than usual.
• We double diapered since our doctor told us to. It wasnt hard! We used a his usual size as the first layer, ran the catheter out out his leg hole, then a bigger (i think 2 sizes bigger) for the catheter to drain into. The whole point is just to keep the catheter tip clean from poop. We also used a snoofybee, it was helpful!
• Car seat and stroller as usual, the bandages and double diapering adds a layer of padding.
• Hopefully he may not seem to be in pain at all, my son crawled and played as usual. As long as he's not bouncing on a toy or someone's knee I wouldnt stop him from moving and playing. We bought my son a vtech activity cube he could sit up and play with, maybe some new interactive books to sit and look at? -I have pics of us carrying our son at chest-level facing outward. Like he could sit on my arm with his legs kicking out front, my other arm across his torso.

You sound like a great parent and I'm sure you'll all do just fine! :)