Finding a loose slot machine is the best thing that could happen to you at the casino. What you need to remember is that just because it's loose for the time being doesn't mean it will always be this way. A loose slot machine is a machine that pays out around 98-99%. Loose machines are always next to tight machines. This is why people will sit at a machine for 5 minutes and move to the next machine over and remain there for hours. The pay out on a machine is based on an average. This means the machine won't give you back 99% of what you put into it, it will pay this out over an average of a certain amount of months. This is also why a machine is never due to pay out. Everything is completely random. Every play you make is determined by the exact fraction of a second that you hit the bet button. Everything is completely random and if the next person who sits down after you wins, don't feel bad because you wouldn't have won. The odds of you hitting the max bet button at the same exact fraction of a second is impossible.
If you are trying to find a loose slot machine, take a look around. Which slot machines can you see from multiple aisles? Generally the higher pay out machines are $1.00 machines. They have the best pay out average. Followed by the $.25 cent machines and so on. Look for machines that are near the concession stand or cashier. The reason they put the machines there is because people standing in line will only be hearing the machines close to them. They will keep hearing the machine going off and paying out. That will entice these people to continue playing. They put the good paying machines by the food because they want you to hurry up and get back to gambling! The longer you are eating, the more money they are losing. They want you to see the people winning good amounts of money- so you hurry up to go back and play the slots.
Sit down at any given machine and play through 10 pulls. If at that time you are not ahead or the same, go to the next machine. If the machine you are on is a tight machine, the next machine over should be a loose machine. Give that machine another 10 pulls and leave if you aren't ahead or even. At that point you need to consider one of two things. Either this is a fluke and one of the machines is a loose machine but not paying out good now, or both machines are tight machines. Watch other people around you, if somebody has been at the same machine for 10 hours, that machine has to be paying good, right? Get to know the regulars. Keep an eye on the machines that they play. People who go there alot know which machines pay out good. Beware because the casinos do switch the locations of slot machines to try and disguise the loose machines. One you find a good machine look it over really good and keep track of where the machine moves to.