Just recently purchased the game, utterly addictive!
Built a 83 level borehole first, just to see what i could find, built some walls to protect me, so i figured to build a base out of it.
Then I glassed over the hole, dug a trench, and made it so the only way out of the trench was for them to run out into the borehole. then I built a gatehouse and bridge, outer castle walls, and so on. No I have to decide what I want for my main fort inside the outer walls, but pausing due to the fact that the wiki out (was going to look up some crafting stuff.