Quick answer: Use a rigid crate with layers or foam wells, put the heaviest boards at the bottom, and avoid piling books on top of delicate scatter.
Car vs train
Cars allow larger crates. Trains favour modular boxes you can carry in one hand.
With your army
Keep miniature trays separate so a sliding ruin cannot shear spears. Army packing: transport miniatures hub.
Frequently asked questions
Foam or no foam?
Foam for fragile scatter; card layers for flat boards.
Can I use a suitcase?
Yes if it is rigid and you add internal walls.
Terrain is bulkier and often heavier than infantry, so treat boards and scatter as separate packs. Keep tall pieces upright where you can, and put a cardboard separator between layers so paint and flock do not rub. If a piece is still curing (fresh glue or varnish), leave it at home rather than rushing it into a bag. If you are choosing new scenery with travel in mind, our 28mm sci-fi scatter terrain guide covers which pieces matter most, and the full 28mm scatter terrain range is here.
For the miniatures that sit on that terrain, see the miniature transport hub — foam vs magnets is a different decision from packing boards.