How to incorporate female and male plugs and solder points

Hello everybody,

I am a student making a project on PCBs ,and i have a small question .

The schematic i want to map ,has many Plugs (both male ,and femlae),and solder points,and connectors (like the EBC15DCWN).

Is it necessary to make a footprint of these parts before going to layout ,or is it only a part of the mechanical layout ofthe board ,and can be added later ?

Can anybody guide me as to how to make the footprints ,or otherwise ? 

Thanks in advance !