The way swimming works is you hold the left mouse button down to start swimming. If you start holding it when the cursor is far enough away (the cursor changes its graphic to show you how far you are) then Naija will do a little speed burst. If you start holding it close, she'll just start swimming normally.
So if you click and aim at a wall at the right distance, she'll leap towards and attach to the wall. You can hang out on the wall as long as you want. Then you can click on/close to Naija to detach, or click far to do a wall jump. Its a good way to dodge certain enemies quickly.
If you hold it and rotate the cursor around Naija fast enough she'll start rolling.
There's a bunch of other lil' tricks you can do, and most have a couple different effects/uses. But I don't want to give too much away.

I was thinking of making a gameplay video. Not another story trailer, but straight up gameplay footage with info on how the controls work. But I wouldn't want to do that until near/after release.