For writing font properties the order is:
style variant weight size family
The order of style, variant, & weight is not critical, but it must end with size then family.
For margins, padding, borders the order is:
When using 4 values: top, right, bottom, left
When using 3 values: top, left & right, bottom
When using 2 values: top & bottom, left & right
1 value will apply to all 4 sides
For background properties the only thing that matters as far as order is the left and right position. The first value is the left position and the second value is the top position. If only one value is declared for position then the 2nd value defaults to center.