I've used it so many different ways since it came out. Originally, I was using the 30 day Psalter and praying Matins and Vespers every day - or almost every day. There were, of course, days that I missed one or the other. Then some months back I started contenting myself with Matins, dropped the 30 day psalter and used the psalms printed and indicated for each day, and prayed it all in the a.m., but that has never seemed right to me. I miss my daily Vespers, and many a morning I noticed myself simply rushing through the vast amount of material to cover and not savoring and heeding it as I ought. So I've reverted back to Matins and Vespers, but without the 30 day Psalter, and it has worked very well. I love the bracketing of the day with both chief daily prayer offices.
I divide it like this:
Matins: the Psalm printed out for the day, hymn stanza, the first reading, the writing, the collect and then the prayer for the day of the week and collect for grace.
Vespers: the second Psalm (indicated, but not printed out in the daily propers), hymn stanza, the second reading, the selection assigned from Book of Concord, the collect and my personal intercessions and collect for peace.
So how are the rest of you using your Treasury? Its versatility has been a real blessing to many!