Preferably, use Process Lasso’s rules to create sticky CPU affinities that persist.
However, if you want to start a program at a specific CPU affinity, you can do so by using the Windows command prompt’s Start command.
start /affinity 0x0000000000055500 notepad.exe
When run from the Start Menu, you would need to include the command shell (cmd.exe), for example:
c:\windows\system32\cmd.exe /C start /affinity 0x0000000000055500 notepad.exe