How can I add a manual currency switcher to my site on Shopify?

[AlexBuzzTV]

Hey guys,

we are using mulitple currencies through markets on shopify. How can we enable a button on the page so customers can manually choose the currency they wish to display and check out in? We've set up the pricing for all currencies we want to use on the website through Markets (native shopify settings). 

Looking forward to hearing back from someone. Ideally we don't want to use any apps, just natively have a button on our page to switch currencies.

Cheers.