Replacing fork on bike but messed up and didn't keep all the pieces in order as I took the old fork off. Which direction do the caged bearings go? What side of bearings face the cup and which side to the cone? Thanks
The key to orienting caged (loose) bearings correctly is to observe that the races do not work together in pairs, but in quadruples.
If it were just a pair (sealed bearings; top left of the figure), the load of the rider (red arrow) would be supported at the axle (black arrow) vertically.
Just one bearing (top left) would in theory be enough. You still need a pair of sealed bearings (top left and right) to avoid sway.
The load applied in loose bearings (two red arrows; bottom of the figure) arises from a combination of the rider weight as well as the clamping force. The two forces are counter-acted by the axle (two black arrows; bottom of the figure). (Hence, incidentally, the axle holds compression forces.)
Comparing the two figures also clarifies why the clamping force matters so much with loose bearings. It can be neither so high to lock the bearings, nor so low for them to be loose. It has to be "just right".
Here I used the term "vertically" on the assumption these are hub bearings, but the same idea applies for the headset if you look at it sideways. The same also applies for the bottom bracket, except that the load will alternate between left and right.