my layout was designed with out a proper drawn plan but in the end it was similar to the sketch and for some reason when I actually laid the tracks I was way out. the layout served me well with a lot of enjoyment, many years passed by and my son has helped me for the last 3 years or so ro revive the layout and we've achieved most of it.
the main object was, to my surprise, the configuration of my tracks and my son came up with idea to change it, at first I was hesitant to change anything it worked for so many years under the control of the Station master but after seeing and the whole project was explained to me I agreed to a change of the track layout and you've witnessed it over the years the new snow modules and other electrification's and changes.
My sons's main objective was to have routes which do or to a minimal extend cross each other and he presented me with a plan and the following explanation which sounded at first a bit over the top because of the extensive work involved in it but we almost got there and when its all together trains will run on their specific route and there is enough room not to get bored.
we will have 3 stopping sites on the 4 outside tracks and a capacity of 20-30 freight carriages and about 12 or so passenger carriage, another essential and crucial part of the change was to have each stopping site roughly the same length so when trains enter the siding the fit nicely into it.
while changing the layout a few stuff ups on my part occurred, having 2 tracks instead of one track on one of the snow module routes, getting the right % incline and correctly placing the isolated tracks down which was determined from which way the trains entered the station.
our trains will run in sequences and because I don't have any hidden stations every train will be visible whether or not all trains can be displayed has yet to be seen as I haven't worked it out yet. Suppose it isn't that hard to get a fair idea, having over 200 locos and with 40 trains running it doesn't look like but most trains on the outer circle may have to run in consists.
on the other hand running trains for a long time one needs to give them a rest, a quick maintenance job and back for duty but in mean time replacement locos can be pulled into service.
another advantage with my collection of trains, I can run 4 different railway companies, SBB+BLS, SNCF, DB and ÖBB some of them could be mixed and these days there a trains from one Railway company going into a different country such is Austria - Germany, Austria - Switzerland, Germany - Switzerland and France - Switzerland. or just trains from one country.
there always will be special trains which don't exist as a prototype configuration, they can be classed as Jubilee trains or any name you can think off.
our trains will have interior lights, traveling passengers, steam, diesel and elelctric locos with sound, electric power from the overhead system one thing I'm not sure when 40 trains are on the move, how the acoustic will play out in the garage with all the sound, x amount of station announcements, horns, whistles, bells, coal shoveling, squealing tracks, squeaky brakes and the cylinder chuffs from steam locos, diesel motor noises and concertos when electric locos engage their electronic torque motors, I'm sure it will not be boring, maybe annoying but hopefully entertaining or it may just sounds like a day out, train spotting. and we can't wait to present you a layout of trains, colourful, inspiring, noisy and breath taking and with some luck will even have the sound knockers raising their eyebrows, lets face it when you're in the city or at a railway station there is a lot of noise going on and we seem to shut this noise out of our head because our concentration is on other things or maybe the noises go up in the thin air whereas most our layout are indoor and the noises are packed together, we will see but for now its all about getting it finished so all these cupboards, filing cabinets, boxes of locos, trains and carriages can be emptied and trains can see the daylight for the first time and with a bit of luck I will see a smile on wife's face for the first time and will she concede at least he stuck to his guns and finished it but one thing I can assure you all, there will be no more, I better not make any promises I may regret it, trains have to keep running and this includes me running with the trains and some cash in my pocket, just in case.
enjoy your trains where ever they are running, resting or just sitting there for no apparent reasons except for the holder of the magic key: It's mine and if it does sound like insanity, I like to hear from one sane person who objects to model trains, including moderators

the original question was: what do you do with your trains: of course there is the the other question what should you not do with your trains: take them to bed or your marital bedroom, put them in your pocket, drown them, submerge them, trying to bend or smash them when they don't work, sell them to keep peace int the house, kiss them, making announcements: Oh my god, she is gorgeous, fall in love, if you can't get enough of your trains don't put them between a sandwich and try to eat them, don't start repainting them, the moment you put a value on them, they loose their sentimental value, don't try to take hours to get the right picture of your trains, the glory is forgotten with the next purchase, never call your trains: toys, it sounds to childish, don't let your trains become orphans, there are many institution and private dwellings who would love to care for your trains and get the rust off their back, never sell a train unless you've got a buyer, the hint is in the wording
John