Make sure that you equip the challenge before starting this run. A good card to have for this is the Well Read Card, which gives you all the codex skills. This allows the traps to be highlighted in red while in a crypt. This is what they look like without the skill (sorry if the image is a little dark):
Turning on the Who Needs a Map? challenge can give you a good notification when you have found a new crypt. The ceiling spike traps are the traps that put the game in slow motion after activating their pressure plates, with Lara having to shoot the supports of the swinging blades. Successfully doing three of these will complete the challenge and unlock the achievement. You can usually find around 1-3 in each crypt. You can reset each crypt's traps by running far enough away from them.