I came across this fact: the word 'solve' comes from the Latin solvere which means to loosen. It got me thinking about getting stuck with writing, aka Writer's Block.
1. Loosen up: stop being up-tight about your stuck-ness. Relax. The world will not come to an end just because you can't think of what to write next, or can't motivate yourself to write another word. It simply won't. It might be inconvenient, especially if you're under contract, but world ending? Nope.
2. Loosen up about what you're writing. It's easy to get stuck because you're worried about getting it wrong. Forget it. One of the first things I tell people is to write rubbish. Writing rubbish is a brilliant idea. Everyone can write rubbish! Write lots of rubbish, and free yourself from the burden of perfection. When you've done lots of rubbish writing, put it aside. When you come back to read it, I bet it won't be so rubbishy after all. Free and easy writing has a lot of energy behind it.
3. Loosen up about finding the right solution. ANY solution is the right solution. As Goethe wrote, "action has magic and power in it", so write down any old solution. If you can think of three possible directions your writing could take, and you're frozen with the enormity of choosing which one is the the right one, then have a bash at writing all three. The action of writing will reveal which is the right one.
4. Loosen up about what is 'right'. What's right for you may not be right for me, or it might not be right for me right now. Loosen up about rightness. There's no such thing as 'right' when it comes to writing. You may have a former English teacher/your mother/your father perched on your shoulder saying you're wrong but there is no 'wrong', just the same as there's no 'right'.
5. Loosen up about your process. You don't get extra reader Brownie points for the first draft being correctly spelt or punctuated. Sure, the final draft needs to be as grammatically correct as you (and an outside editor) can make it, but the road to that final draft is littered with spelling mistakes, typos, grammatical slip-ups, horrible characterisation, ghastly plot errors, boring stuff where you literally lost the plot. And you know what - no one need ever see them!
The blank page IS scary. But once you've made that first mark, it stops being blank. Loosen up, and give it a scribble.