large, small
heavy, light
quick, slow
hesitant
involuntary
I gasped and took an involuntary step back.

careful
shaky, unsteady

go, take
He'd only gone a few steps when he realized he'd left his keys behind.

retrace
You might find your ticket if you retrace your steps back to the car.

step (away) from
She was only a step away from the cliff edge.

step towards/toward
He took a hesitant step towards/toward her.

a spring in your step
I had a spring in my step when I walked into that office for the last time.

a step ahead, a step behind (both often figurative)
He lagged a few steps behind.
She's always one step ahead of the competition.

a step back, a step backwards/backward
a step forward
a step sideways
a step closer
We've moved a step closer to independence.

with each step, with every step
He grew fainter with every step.

dance
jive, tango, etc.

execute, perform
He executed some dance steps for the judges.

learn
keep in
She had trouble keeping in step with the others.

in step, out of step (with)
He was out of step with the music.

big, considerable, giant, huge, massive (esp. BrE)
small
critical, crucial, decisive, essential, great, historic, important, key, major, significant, vital
first, initial, preliminary
final, last
additional, extra, further, next
What's the next step?

logical, necessary, reasonable
We shall take all necessary steps to prevent public disorder.

active
forward, positive
backward, retrograde (esp. BrE)
The new law is seen by many as a backward step.

bold, brave
dramatic, drastic, extraordinary, rare, unprecedented, unusual
irreversible, irrevocable
It suddenly struck her that having a baby was an irrevocable step.

careful, precautionary
faltering, tentative
They have taken their first tentative steps towards/toward democracy.

practical
welcome
immediate, urgent
I shall take immediate steps to have this matter put right.

false
One false step could mean disaster.

number, series

go, make, take
follow
If you follow all the steps, nothing will go wrong.

step in
The move was a first step in establishing a union.

step towards/toward
The talks mark a step towards/toward peace.

a step closer (to sth)
Greece moved a step closer to the final with last night's win.

a short step from sth to sth
It's only a short step from disorder to complete chaos.

a step back, a step backwards/backward
This can only be seen as a step backward.

a step forward
The offer constitutes a considerable step forward.
We seemed to be taking three steps forward and one step back.

step by step
a step-by-step guide to setting up an aquarium

a step further
If he goes one step further with this crazy idea, I'll resign.

a step in the right direction
The new speed limit does not solve the problem, but it is a step in the right direction.

a step on the road to sth, a step on the way to sth

bottom, top
door (usually doorstep)

mind (esp. BrE)
Mind the step!

on a/the step
She paused on the top step.

a step down, a step up
There are three steps down to the kitchen.

front
back
porch (esp. AmE)
concrete, marble, wooden, etc.

flight
You have to go up four flights of steps to get up to the roof.

go up, run up, walk up
She went up the steps to the side entrance.

ascend, climb, mount
descend
go down, run down, walk down
sit on

lead to sth
The front steps lead to an enormous terrace.

step to
the steps to the roof

step down to, step up to
the steps down to the pool

the bottom of the steps, the foot of the steps, the top of the steps