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Hi David,

What's your undergraduate degree in?

It can be quite daunting to find a way in to a discipline you know you are interested in. I remember being in school and receiving terrible guidance from my Careers Counselor on the choices of courses I should take in school to study architecture. Was disastrous and really damaged my application process: he recommend that I study technical drawing over art. 

I've been through my 5 year architecture degree now and out the other side. My interest in the Fine Arts only really started in college and I've  studied painting part time for 2 years which was really a wonderful part of my overall education. Developing your capacity to engage with the visual world is an important part of being an architect, as this is how humans experience their place in the world. I highly recommend that you focus on developing these skills which will allow you to critically engage with the world of visual culture. It doesn't matter if you've never picked up a pencil or if you don't know what oil paints smell like. You will learn. But part of this process of learning is making yourself extremely uncomfortable about what you can't do, and working hard to be better. 

Looking for some sort of work experience in a practice could be useful for your CV, but it could also turn you off the profession if you don't have the luck of finding a good office. The discipline of architecture is incredibly rich, and has much more to offer than what happens in many offices: so if you choose to do this keep that in mind.

Your portfolio is a critical component of your application to architecture schools, so I would urge you to focus on developing your visual and representational skills. I would recommend doing this with a school that offers courses in drawing, painting or whatever interests you most in this area, especially if you are new to these skills. Prioritise developing your analogue drawing skills before attempting to work with computers. It is very rare to see a good digital drawing / image from someone who hasn't developed their understanding of representation techniques.

I'd recommend the book The Practice and Science of Drawing by Harold Speed. It isn't a step by step, but more of a text which communicates the types of things which are necessary in good drawing.