There's nothing worse than rushing to make a flight at the airport and getting stopped at security. And when it seems to happen every single time, it's understandable to wonder what's up. Are you on some secret no-fly list? Did someone tip off security that you'd be trying to smuggle things onboard?

Well, there are actually some pretty common reasons that someone might constantly get stopped by airport security, many of which can be rectified easily.

From trying to pass through security with banned objects and substances to saying or doing the wrong thing in line, there are plenty of mishaps that you can experience before you even board your flight.

Here's a list of 20 things to double-check, and keep in check, to avoid being stopped at security yet again.

20 You Still Have Liquids

It's amazing how many people enter airport security lines with water bottles. It doesn't matter if the bottle is sealed - you cannot bring liquids beyond the specified amount through security. So chug that water before you get in line, or wait and grab a bottle once you pass through.

19 Having Nail Clippers In Your Toiletry Kit

It's easy to forget that your nail clippers are still in your toiletry kit in your carry-on luggage. Technically, you can bring them. But to avoid being potentially flagged, remove them before you head to the airport. You're probably not going to need them anyway.

18 Forgetting to Take Your Laptop Out Of Your Bag

TSA agents are usually pretty diligent about reminding people in line to remove laptops from bags since they need to be scanned separately. Make sure you do this and place it in a tray on its own. And ensure the battery isn't dead either.

17 Oops! Didn't Finish Your Muffin!

You might have grabbed a muffin and coffee to scarf down on your way to the airport, but don't forget that the remnants are still stuffed in a paper bag in your carry-on or purse. Throw out the leftovers of your on-the-go breakfast or finish it before you reach the security line.

16 Looking Suspicious Or Like You're Hiding Something

Being anxious or agitated can come across as suspicious. Try to remain calm while in the line, even if you are running late, are tired, or hungry. Go to the bathroom before getting in line and have a chill attitude to avoid standing out as someone who might be hiding something.

15 Failing To Take Off Metal Jewelry

The airport isn't the place to wear your favourite costume jewelry, metal belt buckle, or metal clips in your hair. Keep it simple to avoid items triggering the metal detector, requiring a more thorough search. Pack the jewelry in your bag and wear it when you arrive at your destination.

14 Sunscreen In Your Carry-On

Packing sunscreen is often remembered at the last minute. Sunscreen is expensive, so you want to avoid not only being stopped at security because of it, but also having it confiscated. Throw it into your checked luggage, or wait and buy some at your destination.

13 Too Many Layers

It might be unavoidable during cold winter months, but limit layers so you aren't sent back again and again to remove this and that. Wear a thin jacket, no hat, and no zippered sweater. If you're cold, leave space in your carry-on to toss in an extra sweater.

12 No One Wants A Chatty Cathy

If you're talking up a storm with family or friends, or trying to strike up a conversation with the TSA agents, this could come across as odd behavior and cause them to hold you back and do additional searches. Zip your lip to get through quicker.

11 Don't Use Certain Words 

Avoid using questionable, threatening, or vulgar language, or words that could be misinterpreted, raise red flags, or be potential cause for concern. Keep conversation to a minimum, period, and leave the casual chatter for after you get through the security check.

10 Whoops, Handing Over The Wrong ID!

Be prepared at security with the documents you need, including your passport and boarding pass. Handing over the wrong ID could make you seem frazzled and raise a red flag. Keep only what you need in your hands and pack everything else away.

9 Treating It Like A Laughing Matter - Be Serious!

Security checks aren't funny. They exist for a reason, to ensure that people aren't trying to bring questionable things into or out of a country, and that travellers have the proper documentation. So keep it professional - this isn't the place to take selfies for Instagram!

8 Acting Rushed, Like They're Getting In Your Way

You might be late for your flight but that isn't their problem. Acting anxious and annoyed, pacing and cursing, isn't going to help your cause. This will only make the security agents wonder what has you so riled up and could hold you up longer.

7 What's That In Your Bag? Don't Bring Weird Stuff

Double and triple check your carry-on bag or backpack to ensure that you don't have something in there that you forgot, like tools, scissors, or other items that might be left over from the last time you used the bag for something else.

6 Fail To Keep Prescription Meds In Their Bottles

Keep prescriptions in official bottles instead of little containers or ziplock bags so agents can verify what they are and that they were legally prescribed to you. This is especially the case if you're traveling for a lengthy period of time and bringing a lot of medication with you.

5 Your Kids Bring Odd Toys, Toy Parts

Kids sneak things into their bags, or they might have broken toys with little parts, including batteries or other items, that are completely innocent but could look dangerous. Go through your kids' bags before leaving and check every nook and cranny for broken bits, remotes, and other things.

4 Changing Lines Without Being Directed To Do So

You might think you're just being crafty and speeding up the process, but this isn't the line at the grocery store. If you switch lines, it might look like you are trying to avoid someone or something. Pick a line and stick to it, no matter how slowly it moves.

3 Having Too Much Money On You

These days, there's no reason to travel with tons of cash on you. Bring only as much money as you will need, plus a bit extra. If you plan to buy something really expensive, sign up for a credit card or exchange money when you get there instead.

2 Not Paying Attention or Being On Your Phone

Put your phone down not only to avoid being rude and slowing yourself down but to prevent agents from wondering who is so important to talk to or what you're posting online. The only reason your phone should be out is if your electronic boarding pass is on it.

1 Acting Frazzled

Sure, maybe you are frazzled because you rushed to the airport, couldn't find your boarding pass, misplaced your passport, the kids are driving you nuts - whatever the reason. But take a deep breathe and calm down. Because your attitude could make all the difference.