Across the slope, like gentle terracing.
But.. if you want to do it the other way, on a shallow slope, you could..
The ideal IMO is that the bed surfaces are level to encourage
water to soak rather than run off.
Beds running with the slope could accomplish this either by gettting gradually taller, or could be broken up in a series of steps, basically mini terraces within the bed..
That is a lot of beds, if you are meaning to do the whole area! Are you growing for market?