First, he grabbed some hi-lighter pens and shuffled them around in his hand, but no soap. I had the right gear, but the wrong technique. So, when you are searching for a sound, try various ways of manipulating your objects. When the script called for footsteps, the old pros had different sounding walks in their repertoire. They could walk scared or angry or just the way Les Tremayne or Agnes Moorehead would walk.
Expression is the difference between a sound effects technician and a sound effects artist.
So, be artistic. The three elements of radio drama are, of course, dialogue, music, and sound effects. I actually rank them in that order of importance. I find music much more vital than sound effects. Music paints settings and pushes the audience s emotional buttons.