The order of operations is a BIG DEAL.So maybe you've heard the saying "Please excuse my dear aunt Sally" and thought your math teacher had lost his/her mind. But that little saying contains a lot of useful information! The letter at the beginning of each word serves as a reminder about which operations we need to do first in our math problems.
The P in "please" stands for parentheses - this tells us that any work INSIDE a parentheses (or brackets for that matter) must be done first when starting a problem. If there is no work that can be done inside a set of parentheses, then we move on to the next task. (Be careful not to confuse the parentheses that we sometimes use for multiplication as the parentheses/brackets that this rule is referring to).
The E in "excuse" stands for exponents (radicals, square roots for example are included in this rule). Any number raised to an exponent should be calculated before you can move on to the rest of the orders of operations.
The M in "my" and the D in "dear" stand for multiplication and division. These two operations are equally important and should be done as you see them from left to right.
The A in "aunt" and the S in "Sally" stand for addition and subtraction. These two operations are equally important and should be done as you see them from left to right.
As with most things in math, the only way to master a topic is to practice, practice practice.
Here is a website with several videos (click here) and endless practice problems (click here).
Here is a website with written directions and lots of practice problems for you to try (click here).
Here is a website that has a few worked examples for you to study and then some problems for you to try on your own (click here). At the bottom of the page there is a link that says "Need More Practice - try our order of operations worksheet generator". You can follow that link and make worksheets for yourself - the website will grade your answers!