Sharing ground and power across circuits
You need to use a Prototyping Board. Most of them have pre-drilled holes and pre-existing copper tracks.

There are different kinds, it is often just down to your personal preference which one you use.

This one is useful for transferring the layout directly from a breadboard:



This one, "Stripboard", is useful when you have several buses, such as multiple power rails, or signals like clocks, data buses, etc:



There are some other ones where there are no copper tracks on the underneath, just single pads on each hole which enable soldering; a wire is wrapped on pins underneath, and a route created directly to the destination, then the wire soldered:



Other boards not shown might include PCI boards etc for direct insertion into expansion slots on PC motherboards, and so on. There are also some meant for small-pitch surface-mount chips.