How to create slider button

I want create slider button which increases or decreases by 10%(i.e 10% to 20% and reversal if we click increase or decrease). I have created slider button in this way

Frame label="SmartPlug" {
    Slider item=Intensity switchsupport

But if click increase button it directly increases to 100%. But I want to change (increase or decrease) by 10%.

How can create slider like that. Should I want to create any rule?
Please help me