Be sure to follow the inflating instructions enclosed by inflating the kayak bladder in the correct order, failure to do this can cause the kayak to twist.
Most kayaks are low-pressure and only need to be inflated to no more than 2 psi so you will not need a high-pressure pump, as they will not register this low and may over-inflate. Simply pump it until it feels hard to the hand for sufficient inflation.
Do not over-inflate or use the kayak under or over-inflated. Make sure the pump has the correct valve type like a Boston valve.
Don’t be fooled if your Kayak looks a little uneven when inflated, this is completely normal and once it's in the water will float perfectly. Always release some pressure if the kayak is being left for long periods either in the sun or in storage, and follow care and maintenance guides.