Sharpes express and PJs are earlies and will need to be used immediately . Try King Edward as a good main crop variety which will come after the otherts and will store well.
Harvest the King Edwards in the morning of a bright dry day. Lay them out in the sun to dry (Don't wash then) and once the sun goes down, put them into a sack.
They need to be stored in a cool, dark, ventilated place. That can be hard to find if its a warm summer. I've had to eat them up in the past when the temperatures are too warm in my shed for storing.
good luck with them and enjoy the new varieties you've bought.