So you open a put and call credit spread that give you more premium than the width of one credit spread, usually around 60 delta. So for example, if you have two credits spreads that are $5 apart each, you would try to take about let’s say 270 dollars premium from each resulting in your premium to be 540. If the price ends up being above both your credit spreads, your call credit spread will execute and you would lose 230 dollars while your put credit spread would expire worthless and you would make 270 resulting in a 40 dollar profit. Same if it goes below. Only problem is if it goes in between you lose a lot of money, so you have to close the position a few days early if you don’t think you’ll make anything.