Learn to eat healthily on a budget. Buy cheap foods, such as oats, brown rice etc...
Check online if you have the best deals for electricity, gas and water.
Check online if you have the best deal for your mobile phone.
Have more nights in with a few cans of beer with mates, instead of going on expensive nights out to pubs and clubs.
Just some ideas

Save 'Treasure'
We all must have experienced this, finding money in locations or things we sometimes forget. For example, such as finding Rp 50 thousand in an old jacket pocket, or even in a backpack that used to be for holidays. Do not immediately spend your 'treasure' like this, you should save well in your savings. Think of it as a surprise fund for additional savings.