Firstly you will need to identify the area in which there is need for a shop - there's no point in opening a shop a 15 minute drive away from an already established shop, so I suggest you get a great big map of the U.K and mark on it all the shops that are already open. This should allow you to see any gaps in the market.
As for qualifications you will ideally have a higher certificate or diploma in animal management, plus the City&Guilds pet store management certificate. A specialist certificate in herpetology, such as those offered by Proteus or Compass would also be an advantage.
In the meantime get as much experiance as you can, and if possible, start building a collection of breeding livestock at home - this way you know that any babies you sell in your shop will have been cared for properly, as well as possibly saving you money in the long run.
Good Luck!
Hannah
