Things to See:

White Temple (What Rong Khun)
Blue Temple
Black Temple (Baan Dam)
Night Bazaar
Singha Park

Restaurants:

Chivit Thamma Da
Lab Sanam Keela
Khao Soi Phor Jai

Bars:

Walk along Nimman Road for a lot of bars
Bus Bar
Zoe in Yellow
Beer Republic

Rooftop Bars:

Johns Place
THC Rooftop Bar
CNX Rooftop Bar