Best way to approach a 3 step approval in Infopath

Hi,

I am creating an infopath form to be published on sharepoint. One person submits it and then there are 3 people that must approve it. They can approve it concurrently.

I want to be able to put a time stamp on it for when each of them actually approve. I've played with assigning different fields at each stage of the approval process i.e. 1stApproval, 2ndApproval, 3rdApproval and they are Yes or No. This just seems messy. I also need to put the time on the form of when they approved it.

Can anyone give me a best approach for this if they have done something similar? Thanks

SJ