So as I said before it is good to write everywhere. To write every little thought that passes through your mind but now its time to organize it all into some semblance of a story.
You can start by writing all these little brief ideas on flash cards, if their really long then keep the paper but add a brief summary on the paper. But remember to write the.m all! Don’t just start discarding them yet.
Start to ask questions related to the note cards like “why can only she fly” ” where did the note come from”. Then begin writing answers for the questions on additional cards working your way through each complicated question to the next.
Then start spreading them out on a hard surface arranging them in chronological order. This may not be how you write the story but it gets your ideas in order and allows you to see where some ideas are too sparse. Remember each thing needs to be explained. If a character has a skill at the end of the book then mention it in the beginning. If you mention something about a treasure in the beginning don’t forget to bring it up again in the end.
If you do want to have cliffhangers look for a reaction and an action that can be separated. They often make good chapter endings but make sure it isn’t too much of a cliff hanger, like if it was curt off mid sentence.