The GAIM score can be entered manually on the Deal screen, both when entering a new deal or when editing an existing deal:
In these four GAIM fields you can enter in any number from 0 to 10. It won't let you put in numbers outside of that range.
Typically you will edit these numbers throughout the sales process as you learn more information about each deal. You can either edit the numbers directly here, or you can include the score adjustments on any entry in the Activity tab under the deal.
For example you can add a Call activity under a deal, you'll notice at the bottom of the activity there are values for the four GAIM scores - these reflect how the score should be changed, so if you put a 1 into Interest, then it will increase the interest by 1. Likewise if you put a -1 in there, it will decrease it by one. So if you called the lead and realized they're a huge organization with lots of uses for your services, you may put a 5 into the magnitude to have it increase the magnitude score by 5.
It's good practice to put the changes to the GAIM score into the Activity entries because that way you have a record of why and when the value changed - otherwise you may be left wondering why deal A has an interest of 8 and deal B has an interest of 1. With a history in the Activity tab, it'll be clear straightaway without having to rely on your memory.
Next Topic: Visualizing Leads with the GAI...