The same way you completed the original one!!!
you have to complete the sinnoh pokedex and get the national pokedex hope i helped :P
Go to Prof. Oak.
He gives you the National Dex.
complete a normal pokedex then go to palpark and talk to prof oak
oak will thank you on the PC that is it what a blow out
you complete the national pokedex
No, there is not a Pokedex after the National Pokedex in Pokemon Diamond Version.
To get your second (national) pokedex you have to complete the first (sinnoh) pokedex by seeing all the Pokemon in sinnoh. when you have, go to the professors lab in sandgem town and show him the pokedex, then professor oak will come and give you the national pokedex.
press switch pokedex on the national pokedex and you will be using the sinnoh pokedex
Yes there is. It should be on the list of codes you start out with on your Action Replay. It will make your Pokedex 100% complete and have all the information on all the Pokemon.
Easy. You just have to complete the pokedex. (Not the national one.) The professor gonna give you one.
pokedex or National