The best book I've read on attention and living in the present is 'The art of noticing' by Rob Walker. I like his approach because it's basically tons of small mindfulness activities baked into everyday life. You start intentionally paying attention to little details in the world more and it's like a flow of creative ideas to keep yourself in a state of wonder about everyday life. It's like being a child again. Seeing things for the first time and taking the time to appreciate them.