Depends on the market. There is no secret formula for all of them. Indicators, reports, etc are all popular ways to do this.
I cover a variety of markets in the thread, not just SP500. Make trade calls in advance. Nothing else like it. https://tinyurl.com/y23rnrro
I think THE most important qualities for success as a trader are perseverance and consistency. When you’re starting out you’re going to lose far more than you win. The losses will constantly make you second guess your rules, but if you change your rules with every loss you’ll never get the consistency you need to improve your trading style. But to be consistent you have to persevere the roller coaster of emotions you’re going to go through. I wish you luck on your journey.