I came out recently with a publishable idea. I analysed it theoretically, and now I need to simulate it - which will take huge amount of time apparently. I wanted to publish the idea, but I can't wait until the simulation is over. My professor suggested to go for a letter journal (each paper has a limit of 4 pages). This is the first time I write a letter paper, and it does not seem easy at all.
Any suggestions or advices to keep the content within the limit of 4 pages without overcomplicating the paper?
I wish this is not a vague question, or too specific.
EDIT: my field is computer science, but the journal is managed by electrical engineers (IEEE Communications Letters - if it is Ok to name it).