Refitting is possible at the POS near the Ship Array and when nearby an Orca/Rorqual/Carrier.
Generally you need to be within 3km to swap in/out modules.
The process is pretty simple:
1) Have any items to want to "swap in" - in your ships hold
2) Click the small triangle under your speedo that points to the right and select "Show Empty Module slots"
3) Drag the item from your equipped modules to your hold to unfit - and drag from your hold to the slot to fit
A handy tip when fitting at the POS is to place your ship midway between the Ship Array and the Corp hanger array. Then you'll be able to rummage through the corp hanger at the same time.
Drones are a little more complicated - you can either have them in your hold (and your ship in range of the Ship Array/Capital) and then right click on them to move them to your drone bay.
The other approach is to open up the fitting manager and then click the drone bay in the bottom left for the window to pop open. You can then drag/drop the drones
