How much do you set aside for 'living expenses'?

[Gigi]

i've been to get help with making a budget, and there are always so many columns, i just don't know how to fill in.

like
presents (your kids, their school mates etc) i make presents, but it still costs money to make presents
dentist (you don't know, until you're there, what needs to be done)
car repairs (ditto)
haircuts
shoes
clothing (only buy to be legal and warm, not for fashion, nonbrand name opshops and fetes are good).

the easiest one to answer is $30 per week for petrol (basically the school run and not much else).
maybe $20 for spending money if it's a good week
i never spend money on water whilst out, take water bottles with us everywhere. Always pack food for a child, they cannot wait "until we get home".

many things i CAN fill in for the budget, regular expected bills, but there is always so much "????" that i have no idea how to fill in.

i really need to have "Mr clip" in my budget, bilby has started telling me "mum, snakes will come" (the grass is high). Keep putting it off.

[Nai]

Per fortnight

Food: 360
Petrol: 50
Bicycle maintenance: 20
Dog food 40
Kids spending 40 (clothes, going out etc)
Own spending 280 (140 each, for going out, alcohol, clothes etc)
Gifts, miscellaneous: 50

I put 300 into savings per fortnight for big bills, holidays and emergencies, And extra onto the mortgage for house maintenance and furniture.