1) Work from libraries instead of coworking spaces
Libraries are free, have books, and are frequented by locals. Coworking spaces don't, plus you can actually talk to people during your coffee break in the chat room.
2) Work from Airbnb for full focus
A good Airbnb has a kitchen, a workstation, a laundry, and a fast Wi-fi. It is better to pay for a slightly more expensive rent than to spend money on coffee shops, coworking space memberships or commutes.
3) Get a gym membership instead of partying and doing stupid stuff
Gym memberships are increasingly cheap. It's a great investment to stay healthy and productive. If you are not into iron, doing bodyweight exercises at home works well too. All you need is a cleaning bucket filled with water (for curls), and a broomstick on top of two chairs (for pull-ups). Push-ups and pistol squats do the rest.
4) Get a transportation card to visit the city while benefiting from free discounts
Long-term transportation cards usually come with many financial benefits.
5) Eat from home
In SE Asia the food is so cheap it is actually more expensive to cook stuff yourself.
6) Practicing intermittent fasting
7) Go to meetup/startup/networking events instead of partying and doing stupid stuff
They offer free food and drinks.
You can cut a lot of monthly costs by just biking: public transportation, medicine, gym membership etc.
9) Cut off your phone/data subscription
Use the power of Wi-fi instead. Do you really need to publish those cute Instagram pictures in real-time?
10) Bank fees
Get cash in bulk from affiliated ATMs.