Stairs

Sure, houses and guild halls have stairs built in. And we could use them. But what's the fun in that? There are many materials you can use to make stairs. Rugs (make sure you can stand on it!), benches, coffins (yes, coffins!), counters, boxes.. I'll try to get some examples of each type over time.

First we're going to look at using benches. For this I chose the Vale Briarwood Bench.
I like to get them all out, lined up nice and even so I know everything's the same size and pointed the same direction before starting
For this example I'm going to use a Redwood Dining Table as my platform that needs a set of steps
Now, select your bench, move it below where you want it to go, and while holding your <Ctrl> key, scroll your mousewheel up to 'float' the bench above the ground. How high? Well, that depends on the height of your platform. (I prefer to start at the top of the stairs and move down, or they never line up for me.) See if your position looks good.
Swing the camera angle around, check it from the side to see if your height looks good. When you've got it where you want it, go ahead and set the bench down.
Now, swinging the camera angle around to different views, I see that my stair is mostly hidden under the edge of my platform. That won't do at all!
Let's try again. Repeat the above steps until you have your stair right where you want it to be. Don't worry, it's a lesson in patience! Once the first step is placed, it gets (somewhat) easier from here. Repeat the steps again, with a second bench. Don't float it up so high, take care to line it up even under your first one, and I usually try to make sure they're touching the one before. Nothing looks funnier to me than a bunch of stairs just haning in mid-air with no support at all.
A straight overhead view is always a good way to make sure you're getting everything lined up right. You can see my bottom step is a little off here.

And always take some time to run up and down your staircase every few steps to make sure everything is lining up right. If you appear to be 'skipping' steps, making them larger or farther appart may help. If you're getting hung up and catching on them, try making them just a little closer together (raising them just a touch higher might help)

Remember, holding <Alt> and <Ctrl> while scrolling will move objects up and down in smaller increments, a full ctrl-click may be too high/low, but a couple alt-ctrl-clicks in between may be perfect.

Good luck!