Do I need to specially follow any process to used Signed DLL of Aspose.Words for .Net other than just adding reference of DLL in my .Net Project?
No, you do not need to follow any special process except adding reference of DLL to your project.
All folders with names, such as net2.0_AuthenticodeSigned, contain the assembly for the corresponding .NET Framework, but the assembly is digitally signed with Authenticode. Note that a signed assembly may load slower than without Authenticode.
Hope, this helps.