Sometimes there are designs where the same circuit elements repeat. The classic example of this is a mixing desk. When such a design exists, it's possible to minimise the design work involved by repeating the elements. Simply copying and pasting won't work, however, as the net names and component numbers are unlikely to match between schematic and pcb designs.
There are two possible arrangements for the schematic elements. either a single sheet can be used, with the element copied and pasted multiple times, or one sheet can contain one element. this sheet is then copied as many times as necessary and each iteration added to a project. In either case, the first requirement is to create one iteration of the module, select it all, then right click and use [Group], [Add to Group] to create a new group. This group must NOT be schematic only, and should be a tight group, though this is not absolutely essential.
This first iteration should now be translated to pcb and laid out in the usual manner, remembering that subsequent iterations will be interlocking with it. At this stage a board profile is not required.
Next, create the extra iterations of the module and use forward design changes to add the extra components and nets to the pcb.
In the pcb design, if not already present, use [View], [Dockable Bars], [Goto] to enable the goto dockable bar. Open the dockable bar, and select 'Groups' from the pull down list at the top. Select the first group in the list, then right click and choose 'Select all matching items'. This will highlight the whole group. Use to select any parts of the tracking which have been missed, remembering that if you also hold down it selects the whole item.
When the whole of the first module has been selected, use to copy it to the clipboard. how go to [Tools], [Apply Layout Pattern] and apply the pattern from the clipboard to the second group. All the components and nets from the second group will be used to build a copy of the first module, which will be left floating under the cursor. Place this as accurately as possible. and release, but do NOT clear the highlight.
Now zoom in on an item, usually a pad, which is known to be centred on the grid. Left click and hold on this item, then use the cursor keys to nudge this into the correct position, which will also snap it to grid. The rest of the module will align at the same time.
Use [Tools], [Apply Layout Pattern] as above for each of the remaining modules.
Now you can add the ancilliary circuits to the schematics and forward them to the pcb so you can complete the design as normal.