1. Miraduoro das Portas do Sol has amazing sunset views :) 2. Take a bus to the Belem Tower and enjoy some natas (aka egg tarts) at Pasteis de Belem 3. Nightlife in Bairro Alto 4. Sinal Vermelho - restaurant that serves really good seafood! 5. Just walk around, climb up stairs, make detours, and you will for sure find something surprising! Lisbon is one of my favorite cities to wander around
*bonus: take a day trip to the town of Sintra (40 minutes train ride from Lisbon) and explore the different styles of castles and the forrested terrain!