Some suggestions for creating drafts on Dreamwidth from these two posts:

• Creating a private community with all posts set to private — Essentially compartmentalizing drafts to one community that can be further organised with tags unique to the community. It also allows convenient full-text search of the whole community and for multiple users to create posts with limited access by changing the community's access filters.
• Saving drafts as private posts in main journal — Centralises all posts, public and private to one space.
• Creating one private post in main journal and store drafts in the post's comments — A way to further centralising draft posts to one link and great for conveniently drafting short posts.