All non-housed electronic parts are vulnerable to static electric discharge, thus to remind you of that fact the sticker is for.
A conductive mat will not be too good when your Kit is powered up and a wristwrap will only put you to a defined ground level, but not your board.
Now for the better part: The humidity in the air will level voltages, so electric shock is mostly observed in winter when the air is cold and unable to hold much humidity. Carpets made of chemical fiber and the plastic soles of your shoed can work as efficient as a van der Graaf generator.
So how get rid of?
Ground yourself at least once before touching the Kit-board using a water-pipe or a radiator. Ground your Kit ba connecting it to power supply and/or USB. Now it will be sufficient to touch the (non-plastic) PC housing to get you to the same level as your board.
I wish you happy designs with your PSoC kit!
that was helpful. thank u :)