>I have noticed my attention span has been shortened and I'm not able to focus on things for very long.
Dump video games.
/lit/sters typically frown on /v/ related pursuits as an art form. I'm not one of them. The arguments against new media mirrors the arguments against old media: radio, film, ditto television. I imagine some of the same criticism was once hurled against the widespread adoption of a form of high technology known as the printing press. My advise is simply about time management. You must make the effort via leaving something else by the wayside.
Putting it another way, don't mix your vices, as Montaigne said.
Take a stab at short stories. Look around for some anthologies, which are typically collections of shorter material. Try out non-fiction works of subjects you might find interesting. Essays, magazine articles, how-to guides, etc. Novelettes are still a thing, and just as damned difficult to write well as a tome.
>Also, how do you guys incorporate reading into your daily routine
Save for when I am on the motorcycle, transportation involves someone else as the driver. That is critical reading time. Just before bed time, or before I fall asleep. Bathroom breaks were made for reading. I tend to camp out in libraries as well, but time here is usually reserved for writing. Unless I am studying something specific such as reference material that cannot (legally) be removed from the library.
>and how do you decide on what book to get next?
Boredom avoidance helps. After finishing a book I tend to move on to something different in scope and style. Yesterday may have been a Warhammer 40k pulp fic, today a Pynchonian postmodern tome. Tomorrow Ulysses, or a graphic novel. Etc.
Read what your favorite writers have to say about works they have read. They may be the best of guides, or utterly surprise you. You're not likely to be bored though.
>Do you always read books to the end or stop if it doesn't interest you anymore?
Stop reading a work? Yep. When you swim through a world of fanfics, and newbe writer submissions there's no choice. It's a question of survival.
For traditional works of literature, I have a high tolerance for difficulty and complexity. I may drop one occasionally, but it's rare.
I hold no loyalty to any series though. There's quite a few series I've not finished, and never will.