Fast UX Process for a register of videogame club

me and my brother are working to a digital registry for a videogame club. the flow identified are

  1. Flow of new client (booked registration)
  2. Flow of registered client
  3. Flow of searching client

The story is : A new client arrives with a pre-registration (he registered on the website with personal information), the staff who admits the people, verifies the pre-registration with phisical ID and if ok, the client become member. A registered client arrives with card, name or surname : some cards are valid for year 2019 and if member does not renew the card, he's not anymore a member. Registered client is checked in by staff to avoid scams or fake names due to law rules, so it is present a feature of search through the database by personal informations.

All the process of checking in / recording new client / searching the client in database must be repeated extensively more than 70 times(some nights reach 140) and the product owner says that is mandatory to not waste time because people in queue get frustated.

The product must be easy to use from staff (nerd entusiast but not too technical), quick and linear as flow as requested from product owner. Staff will have one or two devices (I'm waiting to know if they are PC or Smartphone).

Which tips,material, courses, examples do you suggest ?

How can I speed up the UX ? Are there any UX tips / hacks for many data entry process ? (70 - 140 in a night)