this is the hardware page. here you find general directions about the right Control method.
Looping tools that sit on a table or are in a computer usually are operated by external controllers, often a pedal to keep the hands free.
Some tools have MIDI or 1/4″ inputs to allow calling functions that are not or not easily accessible on their own interface.
consider also using a drum pad controller (like Trigger Finger, QuNeo) or a keyboard – great for accuracy and versatility!
touch screens can be even more versatile and silent, although more delicate and dirt sensitive…
A popular pedal to control a looper that receives MIDI is the Behringer FCB-1010. It is robust and cheap and once programmed, it works for a long time :
interesting also that the creator of those pedals is a livelooper himself and contributed a lot to spread the idea!
here another looping friend created a work around the big Max app that controls the SoftStep
there are more suitable pedals and loads of hand controllers. please contribute your experiences!
Be careful not to buy a pedal that only sends Program Change! those do not send a button release signal and thus are very limited!
Kim Flint wrote a Footpedal Tutorial for the Echoplex which contains interesting information valid for other units, too.