You can copy contacts, in vCard format, onto a microSD card then import them into your phone.
Insert the microSD card (that contains the vCard files) into your phone and mount it (in the Storage settings menu).
Open the Contacts application.
Tap (or press) the Menu Key > Import/Export.
Tap Import from SD card.
If you have more than one account on your phone, tap the account into which you want to import the contacts.
Tap to checkmark the contacts you want to import from the microSD card. Then tap Import and Yes to confirm.