Redirecting Old Site to New Site Same Directory

The script that I have working right now is the one dated 8/1/13, the redirection will still stay the same. Now we have customers that we will need to keep on the old site like you mentioned, how can I add this to the existing script:

This works great but I need to add that script above to this..

 When HTTP Request { 
if { [string tolower [HTTP::host]] equals "oldsite.com" } { 
if { [string tolower [HTTP::uri]] equals"/" } { 
HTTP::respond 301 Location "https://landingpage.com" 

} else { 
HTTP::respond 302 noserver Location "https://newsite.com[HTTP::uri]" 
} 
} 
}