When creating your project, select the dropdown arrow to the right of the project title, and add in a deadline. This will alert all project participants when the project is nearing its deadline and will encourage speedy feedback.
Multi-tasking is a myth. Do your best to block out distractions when working, by turning off notifications and even your cell phone. The less distractions you have, the more focus you can devote to your work.
You simply can’t take on everything yourself. Many of us have an urge to try and be as helpful as possible by saying yes to everything, but it becomes very easy to spread yourself too thin in doing so. Try to only take on things you know you can really devote yourself to.