Find a photo of a building taken straight on so you don't have to worry about perspective. OR stand directly in front of a building and draw and paint it.
The building in the photo was taken last year by me in Spoleto, Italy. I have been wanting to paint it since I saw it the first time. The combination of the old building and the clock caught my eye. I did the painting Wednesday night as an example for my Escondido Adult School class. Our painting topic was beginning buildings.
Please notice that the clock time in the photo doesn't match the time in my painting. I change all clock times to 3 pm because that was my favorite time when I was a middle school teacher.