If you’re building a deck, spend a little time on the ups and downs. That is, give some thought to how your stairs or steps might look.
The standard functional route is to run stringers and nail one or two boards across these for the treads. This technique does the trick, but you may not like seeing the exposed stringers.
Borrowing a technique from inside the house, you could install risers below each tread for a more finished look. Check the dimensions of the lumber you’re using before planning the rise and run of each step, so you don’t need to waste time trimming the riser. When you’re installing risers, make sure the tread overhangs the riser by about an inch.
For long lengths of stairs, add landings to interrupt the run. From landings the stairs can also double-back, creating a more interesting effect.
Where you only need to install a couple of steps, platforms work well. These are like “mini decks” constructed of joists and decking material. You can tier them like a wedding cake for effect. Running the step decking perpendicular to the main decking makes the step easier to see.
If the steps extend down into the lawn or soil, help the transition from wood to yard by varying the materials. First, install wood risers supported by stakes or pipes. Then fill the tread areas with bricks, flat stones, or gravel. The softer the material, the wider the tread. Allow for good drainage underneath.
Railway ties or large dimension lumber make good steps. When laid in soil, rebar them in place. Or build a stringer support system strong enough to hold their added weight.