Don't send empty fields in email

In follow-up to a previous post:
I'm using the following code to send a message to myself when a new record is created.
*****

Dim dkeys

message =""
dkeys = dict.keys

For n = 0 To dict.Count-1
Next
message = message & vbcrlf & "Purchase Order Number:" & dict("PONumber") & vbcrlf

message = message & vbcrlf & "Order Date" & ": " & dict("OrderDate") & vbcrlf

message = message & vbcrlf & "Bill to:" & vbcrlf & dict("BillingInfo") & vbcrlf

message = message & vbcrlf & "Ship to:" & vbcrlf & dict("ShippingInfo") & vbcrlf

message = message & vbcrlf & "Contact:" & dict("ContactName") & vbcrlf

message = message & vbcrlf & "Telephone:" & dict("ContactPhone") & vbcrlf

message = message & vbcrlf & "Email:" & dict("ContactEmail") & vbcrlf
email="me@mycompany.com"

subject="New PO Submitted"
sendmail email, subject, message

*
How do I send only the fields that have data?