I bought a true bypass loop pedal for this - it has 2 pedals on 1 loop (boost, analog delay) which is my lead sound; the other loop is for modulation effects.
If the effects you want to turn off an on are all in the same signal chain together, a loop pedal will do like the iguana mentioned above. Otherwise, you'll need a programmable looper, such as the Ground Control, Gigswitch, or others. Depends on how deep your pedal changes are as well as your budget.
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