Not hard at all.
First, you print the Orcad schematic, preferably 'D' size. A BOM will
also be very helpful.
You then open Protel. First, you create parts for all the elements
listed in the BOM. Then, starting in one corner of the printed Orcad
schematic, you place the new Protel part in that position on your new
Protel schematic. Mart the part with a sharpie. Then place the next
part, and connect the two. Repeat until you have all the parts and
connections on your Orcad schematic duplicated in your Protel schematic.
Or, you can go through translation software and import/export nightmares
that take twice as long, and give you more errors...
Charlie