1) I place one uncoupling track per yard track, just after the switch and any curved track you may use to space your yard tracks. You use the shunting engine to move the cars to be uncoupled over the uncoupler track to uncouple. Then you sort the cars you want together on an empty yard track. This is the logistics of creating a cut of cars in the order you want to build a train.
Cars can be coupled without using an uncoupling track. with conventional lionel type couplers, you need to impact the stationary cars at about 8-10 SMPH in my experience. (depends on the stiffness of the specific couplers)
3) I have minimal operating accessories in the yard. On my layout I have engine servicing on one track, an icing station on another track and a string of industries on the track closest to the wall. These industries with loading docks are kitbashed building fronts. The rest of the tracks are for storage only. There is one empty track, which on my layout goes to the engine servicing area and roundhouse. This track is used as temporary storage to build trains. Building trains is like a moving puzzle, you need an empty track to move the other cars onto, otherwise you can't easily build a train, with no empty place to put the cars.
4) I have a lead track that is a little longer than my longest yard siding, which means I can back trains from the yard and switch cars from siding to siding without fouling the main line. This track runs parallel to my main line in order to conserve space. On my layout the yard lead goes around one of my corners, which was required due to the location of the yard.
5) a train entering the yard needs a place for the engine to "escape". I run the train into the turntable lead track, where the engine can go to the turntable. If you do not have a turntable, then you will need a set of switches at the end of two of the yard tracks in order to do the same thing. This takes up considerable yard space, however it is what is needed to properly operate the yard.
Good luck. If you post your RR-Track layout, it will be easier to comment and make suggestions
