Writer's block is what you might call an occupational hazard. It is very likely to happen.
Whether at the beginning, middle or end of your writing project you will have a moment where all that stands between you and a page of inspired writing is sheer empty, sometimes vacuous space.
Wanting your piece to be perfect, fear of putting your idea forward to be critiqued by others and simply just not being the right time are other factors that can hinder the creative process.
So how do you overcome this? Well, becoming overly frustrated will definitely not help. Deciding that you’ll just wait until you are ‘in the mood’ or inspired won’t help either. Watching TV and making excuses will also not serve you well.
What can help is the following:
Exercising - go for a walk or a run, something that will get oxygen flowing.
Getting rid of distractions as much as possible.
Move! Change your environment.
Make it habitual. Having a routine around your writing will help to stoke your imagination.
Listen to music.
Call a friend to help you relax.
Have a brainstorming session and list your ideas.
Write everything and anything just to get going.
Don’t overthink the process, just make a start and see what happens. Creativity can be hit and miss. Not everything you write may be worth publishing but the more you write, the more chances you have of getting it the way you want it and having a piece of work you can be proud of.