Minecraft wiki entry for Survival_in_an_infinite_desert, associated text: You need to mine 52 blocks of sandstone, 208 sec, about 3.5 minutes. Possible to do in one day if you are efficient and focused.
Build a small surface shelter to prevent mobs from entering, with a 1x1 skylight.
Bring a huge stack of sand.
Inside the surface shelter, dig straight down beneath the skylight, watching the sun.
Each day when you need to get back, pillar jump back up the shaft using the stack of sand. Time this operation so you get used to how long it takes.
Once you reach the bottom, create a mob-proof shelter as per the single staircase.
Then create an open passage running away from you, of at least 24 long × 1 wide × 2 high and wait for creepers to spawn.
Drawing creepers down the shaft is not possible, you just have to wait for them to spawn, and deal with everything else that spawns.