How to make a budget and savings plan

Dear Dr Pesa,

I just got a job a few months ago and moved out of my parents’ home. My net income is about Sh20,000 a month. This was sufficient at first but now, I don’t know where the money goes. My rent is Sh5,000 and other monthly expenses that include electricity and water bills add up to Sh1,000. I have a major issue with budgeting, and I suspect that’s why I am broke by the first week after payday. Do you have any budgeting tips for me? Also, can you help me draw up a budget plan based on my salary?