Excavate ground for sleepers of bottom step with mattock, spade and shovel.
To make frame for step, cut a 1.2m length of sleeper to use as a riser. Cut side lengths to suit your site, remembering to make outer curve lengths longer than those on inner curve. Screw riser to sides.
Put frame in place. Check it’s level crossways but with a slight downhill slope so water can run off.
Continue working up the slope, excavating and building a frame for each step individually. This way, you can adjust depth of each step as you go to suit slope of land and curve of stairs. Don’t be tempted to alter riser heights, as this will only make steps uncomfortable.
When all frames are in position, check each is level, then secure in place. Where step sides run on top of each other, join them using sleeper offcuts as cleats. Screw at top and bottom to secure. Use narrower cleats where the angled sides cross. Where steps finish at top, box in to hold gravel.
To ensure your stairs won’t shift, hammer in star pickets against inside edges of each side, then screw pickets to frames.
Partly fill stairs with a layer of rock rubble, such as crushed sandstone, which will drain well.
Spread a layer of road base on top of rock rubble, levelling it roughly with your shovel.
Compact road base firmly. We made a compactor from sleeper offcuts.
Top with a 50mm layer of crushed granite and spread with a float.
Dampen granite using a fine hose spray then compact with float.