Home improvement - painting and such like

I'm opening up a blog post for a slightly unusual topic. Decorating. We're planning on finally getting round to decorating our house (It was a new build 2yrs ago, so everywhere is builders magnolia that's as thin as skimmed milk) and so the choices of what to do, where and how are all starting to bubble up between me and my wife. (We've not even asked the kids yet, as who knows how many more options and choices that will open up!)
So, the main choices we're trying to come up with are:

• Where to start - What room should we try first!
• What to do - painting, a bit of wall art, wallpaper
• How to do it - Tips and tricks on making it easy (!) and the right way to do things.

So I'm also after comments too, so feel free to let me know tips or tricks or any suggestions you have on how we should do this to give a good result.

My thinking so far:

Where to start - Probably our master bedroom, it's at the top of the house with adjoining en-suite and has low ceilings and strange angles/corners (It's built into the roofspace of the house). Initial thinking is just to paint, but for a bedroom what colours to go for. Light colours would make sense, it's not got a huge window so increasing the room light by paint would be better (No dark oaky types), our furniture is also light wood colours so keeping it light. Light grey colours with a feature wall with extra colour seem to be an idea that keeps coming into my head, because of the strange shapes of the ceiling though not sure how you would approach this. Other colours such as light pastel colours would maybe be an option?

What to do - I think wallpaper is discounted, as I hate the stuff, hate putting it up and removing it, so I reckon this one isn't going to be an option. Wall art, possibly, we did this in the children rooms and it looks really good, but not sure it would fit with what we want for our bedroom.

How to do it - This is the thing. I've never been a great painter or decorator, so I just do what I think is right. Go and buy a load of masking tape, and mask along the skirting board, and along the ceiling, around light fittings and electrical sockets. Then get a roller, slop some paint in the tray and roller away, trying to keep it even. Do you keep the strokes up and down or side to side? How thick do you apply the paint? And when I get to the fiddly bits and get a paint brush, how do you make it look the same, brush strokes always look different and it looks like you've 'highlighted' the socket you've painted around since the brush strokes stick out more! This is the bit that I always struggle with! So this is the part that needs the most input from those that know better, so I'm hoping somebody hears my struggle and tells me the right thing to do!

I look forward to comments or suggestions :-)