From Delivery Hero Facebook:
"We are back with the Tuesday deals! Order from our selected restaurants and pay up to 50% less on your favorite food! Offers valid only between 5pm to 10pm today.*"
Participating Restaurants will have a code displayed in the restaurant name and cart. Enter the code on checkout to apply the discount and pay with Credit Card/Paypal. Look out for restaurants that have a red % symbol or filter for Deals. Click on the symbol to view discount.
Full T&Cs here