Build for the target (x86/x64) and use an elevated developer command prompt:
Register
> regsvr32 MyComServer.dll
Unregister
> regsvr32 /u MyComServer.dll
Consume MyComServer after registration
using System.Runtime.InteropServices;
var s = new MyComServer();
Console.WriteLine(s);
[ComImport]
[Guid("07654321-4321-4321-4321-BA0987654321")]
class MyComServer;