There should be a thread with loads of keyboard shortcuts and tips and tricks somewhere on this page.
Ctrl + L-click = selection tool, + R-click = magnifier.
Alt + W in mixer to switch between meters and waveforms.
R-click then A on (almost) any knob or slider to create automation clip (which will be as long as your complete tune OR selected area of tune).
Simply Middle click or R-click then R on patterns or channels to rename / colour.
Use the sequencer for simple repetitive things or when you need a series of hits in different velocities / pitch (there are buttons in the top right corner that let you adjust pitch and velocity for each hit on the selected channel).
Alt + arrow keys to move channels left or right on the mixer.
Things I usually do which I think is really really helpful:
I recolour patterns and samples in the playlist according to the feel and timbre of the different sounds. Hats and crashes are usually yellow, sometimes bright blue, shakers usually bright blue, rides and sort of techy or glitchy sounds are orange, bass is usually deep blue or purple, drums will be given colours according to their feel; tribal drums are often green, breaks have clearly distinguishable colours if I switch between different ones a lot, etc ad infinitum. Same applies for mixer channels.
If an instrument has automation I chuck the automation clip right underneath that particular instrument's channel in the playlist window.
Any channel that is sent to a bus has the prefix "-" (without quotes..), if practically possible, the bus is placed to the right of all the channels that are sending to it. The bus channel is always coloured pink with the prefix "+". A bus with several buses busing to it has the prefix "++" and usually a deeper shade of pink. Channels that are split have the source channel prefixed "-" and the "cloned" channels prefixed "/" and are usually coloured orange.
In the playlist window I usually have all my drums at the top, then FX and stuff, then bass, sub and finally pads and things. Pads are usually coloured bright blue.
Using this uniform system really helps me keeping track of what's going on, keeping a minimal of different instruments, or at least different kinds of instruments, on each channel in the playlist helps a lot. This regime is flexible when it comes to different parts where some elements are completely absent and some show up for a one off performance, ie the breakdown might have a completely different set of drums, the hats replaced by rides and a synth that is never heard in anywhere else in the tune.
Those are my workflow tips off the top of my head, but as with everything it all comes down to getting accustomed to using the tools in front of you over time.
Oh; and L-click and then M to make new a copy of a pattern or sample, U to make the sample "unique as sample", ie rendering it as audio and saving it in your samples folder for ever and ever and ever.
Backspace to swap between snapping to grid and placing tings wherever you like, there's a little box in the top right corner of the playlist window to zoom in and out vertically, mouse wheel while over the bar that shows what bar you're on in the playlist view to zoom horizontally.