When writing out my story I can't really seem to get the story moving by having an idea ALONE, so what I like to do is create "open loops", which are ideas that are presented without conclusion that are looped back to a bit later. For example, I know that my latest plot involves the main character saving someone he sees like his younger self, and then after saving his younger self moves onto being inspired to save the world. The plot idea alone if I was to approach it entirely linear would be rather flat and predictable, but by adding in open loops I can keep people guessing and have them eventually realise that the main character has grown without me telling them explicitly. Each chapter I write I am struggling, and I struggle because I really WANT to just TELL people what happens but I am stuck needing to write compelling story that SHOWS them what happens. What I have started to accept is that you have to write in open loops, and you have to leave some things unanswered... It is so hard! I just want it to be done already! But good plot requires constant thirst and hunger being created for the audience, and I think I am finally understanding how important that is for not only the story but finishing it also.
I'm not sure I really understand what you mean by 'open loop.' Could it be you're planting questions in the reader's mind? If that's the case, you might find it helpful to read Techniques of the Selling Writer by Dwight V. Swain, Chapter 4: Conflict and How to Build It. If that's not what you meant, please ignore this post.
Your "open loops" is what creates your story. It makes the reader want to know what happens next. As long as you close these loops sometime in the story, the reader will be satisfied if you have a good ending. Map out your chapters so you know when you open a loop and when you want to close it. This should help you with anxiety to tell the tale all at once. Patience is a very hard virtue to grasp when you are telling a story.
Are these open loops also called subplots? I agree with @Raven484 , that patience is required to tell a story. If you're struggling to be patient and want to get to the end ASAP, just pretend you have an audience in front of you. Pretend that what you're writing is something you're verbally telling them. Watch their reactions as you tease them and pull them along. You're not going to say "Good evening ladies and germs, I'm going to tell you a story. It's about a guy who saves another guy who reminds him of himself when he was younger. Then he goes on to save the world. The End." So don't write it like that either. Start small and work forward, but keep that entranced audience in front of you the whole time. At least in your head. You're not spitting out a plot, you are working magic!
I do not know if I'll go with "subplots" as the description for minor characters who make appearances later on and have progressed based on prior actions, but it is refreshing.
Definitely leave things open. One of the golden rules of entertainment is always leave the story open for more. Now, the sneaky thing is you can re-open the plot from a quite closed ending, but it is usually more effective to always have new things and/or unresolved lines.
