Shopping arcades will bring in one-way systems and limit the number of customers to safely reopen after the coronavirus lockdown.
The Welsh Government is set to update its advice to retailers on 18 June, but shops in England can reopen on Monday.
For Cardiff's shopping arcades, which are indoors and narrow, there are extra challenges to be overcome.
The council's cabinet is set to discuss on Thursday the plans to "reopen" the city centre.
The Morgan Quarter's two arcades - the Royal Arcade and the Morgan Arcade - measure only 10ft (3m) across and are connected by an even narrower passage called Tabernacle Lane.
The arcades are home to independent businesses, including cafes, restaurants, record stores and shoe shops.
They will all have to abide by social distancing rules once they are allowed to reopen.
To prepare, stickers have been laid on the floor of the arcades to mark out two-metre gaps between shoppers and a one-way system will run around the two arcades.
'We'll still be here'
Rory Fleming, the manager of the Morgan Quarter, said security staff would be stationed at the four entrances and exits in order to limit the amount of shoppers.
"The arcade's only three metres wide... that's why we've brought in the one-way system to safeguard both the shops and our customers throughout this period and beyond when we do reopen," he said.
"There will be no outdoor seating in the first period for the likes of the cafes and restaurants, just so we maximise the amount of space we do have.
"We've seen it in the supermarkets. Before lockdown you could walk freely anywhere within the supermarket and in the majority of cases [now] everybody is abiding by the one-way system. I think certainly for the rest of 2020 this could be the new norm.
"These arcades are two centuries old and there's a lot of resilience in these walls," he added.
"These arcades have seen two world wars, they even saw the last pandemic and we're still here and we've still got a lot of good independent businesses.
"It is tough at the minute, but you can see that if this arcade can come through those three events on its own, we'll still be here in the next century."
Staircase traffic lights
Steve Salamon, who owns Wally's Delicatessen and Kaffeehaus in the Royal Arcade, said the measures would be a "big change" for customers.
He said he had introduced a one-way system around the shop, with separate entrances and exits, and sneeze guards at the tills.
The number of people who can come into the shop will be limited.
The site also houses an upstairs coffee shop, but - unlike other cafes, bars and restaurants - arcade-based businesses are unable to use outdoor seating to boost capacity.
Mr Salamon said: "We are allowed to do takeaway and we are at the moment working on a takeaway menu and a system for customers to place orders, to pay for the orders, and wait for them to be delivered in a safe, socially-distanced manner.
"Our coffee shop happens to be up a narrow set of stairs so it's not going to be possible for customers to go upstairs as things stand at the moment. [Outdoor seating] is not really viable in a narrow, arcade environment like this."
He said new ideas, such as a traffic light system on the stairway for staff and customers, could be introduced to allow safe access to the coffee shop in the future.
Not-for-profit group For Cardiff works to improve the city centre.
Its executive director, Adrian Field, said: "We hope that when businesses are given the green light to open that customers and workers will embrace them and work with them in supporting the economy and that everyone takes on board the advice provided.
"Businesses have already shown that they can adapt quickly and they will have to continue doing so.
"Collaboration, communication and reassurance are key to ensuring that businesses ride this storm."