However, you should acclimatise the splashback prior to installation to allow the adhesive tape to warm up to +10°C, this ensures it will bond correctly to the substrate.
If you have a gas hob, you'll also need to ensure that the hob is installed correctly to prevent direct contact (or close proximity) between the flame and the splashback, a distance of 100mm from the face of the splashback is considered as safe.
Make sure to hold the splashback up to the wall before fixing to ensure you're happy with the position aesthetically.
Apply a clear, neutral (cure low modulus) silicone adhesive, like CT1, to the rear of the panel and remove the covering paper from the adhesive tape.
(Avoid using acetoxy or acetic curing adhesives as they can become visible once the adhesive is fully cured.)
Carefully position the panel in place and use masking tape around the edges to temporarily secure it in place whilst the adhesive cures.
If the splashback is sitting on top of a worktop then you can apply a thin line of sealant along the back of the worktop where it meets the wall to seal any gaps.
If it's not already supported, then use a timber batten to support the splashback whilst the adhesive is curing. Otherwise, it could fall off the wall.
Finally, once the adhesive has fully cured, remove the masking tape and apply a thin bead of kitchen suitable silicone sealant along all of the exposed edges to seal it.