How do you get yourself on writing again after a long time of not writing?

I use my writing rituals and what inspires me to write.

I have not experienced that because I always write.

I start writing anything , even small drafts 

This question does not apply to me yet at the moment but if it happens in the future, then I feel it would just be another assignment that I must perform and used off.

The best way is to go over the pieces you wrote in the past; remember the circumstances that drove you to write. This will give you a good idea to of the "stimulus - an element that drove you to creative process" and "response - how and what you wrote." Another important factor is to equp yourself completely with what is in demand and where do you stand now in meeting those demands. Each "coming back" needs concentrated eneegy, attention and the will to create.