(DISCLAIMER : I am nowhere an expert, I am a mere potato who has gone through (st)age 21.)

Let's face it. Life didn't come with an instruction manual, and although some of us may have been lucky enough to have an intact family and a close circle of friends, many still face uncertainty in their alone time.
(Raise your hand if you feel like your life feels like a Sims game gone rogue haha)
While I may not be 21 anymore (23 here and in a very beautiful relationship with my soulmate) here are some things I wish I knew and some knowledge I've picked up along the way:

It's Okay to Be Single :

Just because you don't have a boyfriend or girlfriend yet doesn't mean you'll be single forever!
Sure, other 21 year olds may be all smitten and have gone marshmallow when their phone rings or they're all lovey-dovey in social media, heck - some might even be engaged already!
It's okay to be single at age 21, and by all means - enjoy yourself!
Go out with your friends, study coding or learn a foreign language or two, practice your guitar or piano, travel, and even party!
Enjoy all the things that life has to offer to you but please don't hurt yourself.

Cherish Those Who Are Around You

Being or becoming 21 years old is going to be the stage in your life where you should probably be shooting lasers out of your eyes or change the weather through your emotions if you were a mutant (if that is happening to you right now then I highly recommend that you call up or visit Professor X!)
Age 21 is like a training ground... This will be the time where you will know who stays or goes in your life.
It's like a tall pitcher of lemonade just waiting to spill over! You will be meeting various people, people who will either help you reach your goals or people who will ruthlessly tear you apart, yes - even your family members will get on the action!
Now, once the dust settles down... You'll be surprised that there will only be a handful who will be with you at this crucial time so it's important to cherish them: go make fun of your boyfriend or girlfriend by sending him or her random memes, puns or heck, tease them by calling them by their first name (evil grin). Hang out with your true friends no matter how small your circle is, play some games, laugh at memes, watch movies, go on a hike until every drop of water in your body evaporates and eat all the pizza you can!

Don't Join the Rat Race

Some of us may be on their way to building their own company, getting married, migrating abroad or getting their big break while others may still be starting out in life.
This notion of this rat race or diploma mill isn't applicable to everyone: some have no means to go to college, others may have chosen to work instead of going to school so that they could help out their mom or even their whole family. The truth is, no matter how much you prepare, some things we have planned will not always go our way, but this doesn't mean you should stop going after those goals. If opportunity doesn't knock, build a door. (wink wink)
Again, there are no shortcuts in life and roadblocks shouldn't hinder you from achieving them; don't be afraid to take the road less taken. Take baby steps if you need to but don't ever stop.

Save Some Money

I seriously regret not doing this when I was younger but due to the fact that my dad had cancer and we were drained financially, perhaps I could excuse myself a bit.
While it's okay to spend and even splurge some on yourself when you get your paycheck, it would be nice to set aside some money, even if it's only spare change, so that you can have something for the rainy days, emergencies, or in case your bank decides to play tricks on you and delay your salary cries in corner (how much is a soul worth nowadays? I'm joking).
You don't necessarily have to drop PHP100 in your piggy bank, start small... Say PHP10 or PHP50 per day.

Learn to Say NO

And lastly, the most important lesson of all . As much as we'd love to take on everything life throws at us by saying YES to every opportunity that comes, sometimes... We have to say NO.
It's not wrong to accept opportunities presented to us but sometimes, because of our eagerness, beneath all those opportunities is also our poison.
As I've mentioned above, you will meet a lot of people but not everyone will be your friend. Don't wait for your body to shut down from exhaustion or wait for something really bad to happen, if you feel that it's not right, say NO, there will always be another chance or a better opportunity to come.

See ya around,
Rel-chan