Q:

How to get user first name in Sharepoint Designer 2010 workflow?

I would like to get access to the current user first name, so be able to insert into an email.
I have found that
[%Workflow Context:Current User%]

will insert the full name of the logged in user (LAST FIRST MI in my case).
Is there a way to get the first name of the user somehow?

A:

Select "Add or Change Lookup"
Select "User Profiles" under Data Source
Select "First Name" under Field From Source
Select the default "Field:" option
Press the fX button 
Select "Workflow Context" and "Current User"

Hit Ok and you should see something like [%User Profiles:First name%] appear which represents the first name of the current user.

