Take an old toothbrush or paint brush and with water rub off the mealy bugs, then spray the neem oil soap nut solution. 5ml neem oil plus soapnut solution or if you don't have soapnut a few drops of liquid dishwashing soap to a litre of water.
Repeat this for sometime till you see they are eradicated.
You can also keep the plant 6"from the base of the soil free from any leaves or branches.
When the soil is too wet or if you water late evenings the pest infestation is more active
I have even used aloe Vera Juice to remove the mealy bug infestation and it has given amazing results, you can try that too.
Good Luck.