fiddle around

Fiddle around means to spend time in aimless or unproductive activity, often with a connotation of tinkering or puttering without clear purpose.

I spent the afternoon fiddling around in the garage.

It can also suggest experimenting or making small adjustments to something: Stop fiddling around with the settings and just leave it alone.

The phrase implies a lack of seriousness or focus, sometimes with mild disapproval from observers who think you should be doing something more useful.