What is the best to clean your PCB (Printed Circuit Board)?

Things you need:

Thinner (used in mixing the paint)
 Iso-Proply Alcohol
Acetone
3 Brushes (small and harder)
1 Tooth brush
1 cotton cloth

I follow this procedure below:

After etching the PCB and soldering the components, the flux remains and PCB looks kind of un attractive. Keeping flux for long time can accumulate dust hence there are chances of corrosion.

Above picture shows flux remains after soldering.

Now step 1: Using hard brushes apply thinner on pcb quickly without getting dried. After applying use the tooth brush to brush the flux off. Remember thinner should not get dried. So do remember to apply thinner every 5 seconds after brushing with tooth brush. You'll notice the flux getting dissolved in thinner and disappearing. Keeping the thinner wet on pcb clean it off quickly using cotton cloth. Keep it for drying.

Step 2: After getting dried, if you did not cleaned it quick your pcb will be little sticky. Thinner gets sticky after drying. So apply acetone with another hard brush. And wipe it off with cotton cloth immediately before it gets dry. Your stickiness will go away. check for sticky spots again and clean them. After cleaning keep it for drying.

Step 3: Apply Iso -proply Alcohol to clean it furthur. Keep for drying.  Congratulations You PCB is ready and cleaned. Iso- Proply Alcohol can also be used to clean pcb before soldering. Do not use thinner before soldering.

You will have a flux free PCB.