This apply for all type of Minecraft, either on PC, Xbox, or Pocket Edition. I am using PE Minecraft. Also, you could make this in survival or creative mode!
Step 1: Create New World
Click play and on top, click "New"
Thn, put name and remember, seed "911" because there will be a "sand cave" to make our shelter!
Step 2: Generating
Generate our world and wait patiently!
Step 3: Got In
This is how our world going to look like when we first got in!
Turn to your right side now.
Step 4: The Sand and Stone Hill, or "Caves"
Turn to your right side and find the exact same thing that in the picture! Because of the seed we used, all our worlds are looking exactly the same thing as each others'!
Step 5: Closer Look at the Sand Cave
Ignore the stone hill! Go to the sand one, you see a small cave there, right?
Step 6: Light It Up!!!
Use torches to light up the cave. Be careful of the loose falling sand! If it fall down, destroy it and use sand stone to make a bigger cave and roof it up!
Step 7: Make Some Walls
Make your own wall! If you want your shelter to be big, make big walls, expand it out! If you want it tiny and compact, make the walls smaller. But I recommended big, 'cause we gotta make space for decoration and stuff!
Step 8: Glass, Glass, and Glass!
If you are in survival mode, you have some disadvantages. First, the loose sand, then the zombies, and creepers, and skeletons. It would be good to have some glass for a good window to look out for the explosive creepers! :))
Step 9: Final Step Ain't No Step
Yep! Just decorate it like the way you want!
This is mine in a different world! I have the whole big glass to look, but too bad I'm in creative! *laugh* Enjoy your natural shelter!