
When my oldest daughter was turning 7, she requested to have a mermaid birthday party. She pretty much was a fish already all summer long in our pool, so it seemed like an extremely fitting theme that I was more than happy to get behind! We already knew that it would be a pool party since, well… August! It’s usually broiling hot by that time of summer when our party would take place. Come along, journey with us far below the sea (ok, maybe just underneath the pool-side pergola!) and discover budget-friendly, fantastic D-I-Y party activities such as cookie decorating, sand art, piñata, hair chalk, photo ops, and more! Learn how to create The Most Magical DIY Mermaid Party!
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Most Magical DIY Mermaid Party Invitation
First things first – I went to work finding the cutest invitation that would inspire everything else for our party! This is always my first order of business when planning any party – finding that invitation inspiration! You can follow my steps to creating DIY birthday parties using my Party on Fern E-Book Workbook/Guide! For this particular party, I found this stunning invitation!

I just LOVE all these shades of purples, blues and green with hints of iridescent shimmer and gold. Seahorses, starfish, shells, coral reefs, and of course a mermaid fin would all be incorporated into this party’s party decor.
DIY Mermaid Party-Themed Cookies
Leading up to the party, my girls and I baked our favorite sugar cookies in these adorable under-the-sea shapes: A Mermaid Fin, Starfish, and Tropical Fish! We used our favorite Ultimate Fool-Proof Gluten-Free Sugar Cookie Recipe, as usual. It’s always fun getting the kids involved with the party prep, and baking ahead of time is an easy and fun way to do it!



A few days before the party, we decorated some of the cookies with a friend who wouldn’t be able to attend the party. Girls had fun decorating with the blue, green and purple sprinkles.
Most Magical DIY Mermaid Party Setting
Now, you don’t need to have your own pool to host a mermaid party – you could host one at a community pool, a lake, or even at the beach if you happen to live close to one! I think that would be the ultimate! You could also think to ask a friend or family member that has a pool if they would be up for hosting or letting you use their pool for an afternoon. You might also think about having inflatable pools for little kids or some simple water games and sprinklers set up.
Party Setup
The setup for this party was fairly minimal, due to the fact that it was taking place outside in our pool area. I hung a large birthday banner across our pergola that I originally painted and used for my daughter’s very first birthday party hosted in our barn. It’s great being able to reuse things over and over again. I used one blue fringe foil curtain backdrop for a “ocean look”. If I could do that over again I probably would’ve ordered way more to go across the entire back of the pergola. Oh well!
Up on our deck on one of the tables, I arranged a few mermaid things I found within our house – a mermaid snowglobe that my daughter made that year (full instructions on personalized DIY snow globes HERE), a fun caricature of my daughter as a mermaid, and found some light green netting at the dollar store that I draped across our white tablecloth. I also put our party invitation on display!
We originally chose some mermaid-themed party supplies from Target, however most of them are unavailable now (since this party was years ago) so I’ve linked similar ones! I then set up one table with a shimmery mermaid-scale looking tablecloth underneath the pergola where I would serve cake and have the kiddos decorate cookies. These iridescent mermaid party plates and napkins worked perfect with my color scheme.
I hung blue, purple, green and white balloons on our pergola’s sides, and along the pool’s fence-posts. We also had a cute seahorse and mermaid balloon. These balloons are similar and also very fitting with the color scheme. Another kit I really like that could be used for making a balloon garland are these. We also fastened our seahorse piñata underneath. I was trying to link the seahorse but I found this cute sea turtle one that would work perfectly instead!
Mermaid Party Outfit
Of course, every mermaid deserves a celebration that’s as magical as the sea itself! We decided our birthday girl needed to become a real mermaid on the day of her party! She chose a bikini set which included a mermaid fin and tiara similar to this one. We also provided hair chalk for anyone who wanted to play around with the color of their hair and make it more “mermaid-esque”!





Most Magical DIY Mermaid Party Photo Op
My kids Nanny painted this sweet under-the-sea scene for all of the kiddos to pose behind. They loved taking turns getting their picture taken as a mermaid!

Sand Art Activity
I set up a Sand Art craft table on our upper deck area. Kids loved this easy and fun activity! I purchased colorful sand and little mermaid fin shapes for them to fill. I tried to link what I used, but unfortunately the exact ones I found are currently unavailable; However, these shell-shaped bottle necklace kits are ocean-themed and would work beautifully!



Mermaid Party Cookie Decorating

Most Magical DIY Mermaid Party Dessert Time
Since my daughter’s party falls in the month of August, for years it’s been our tradition to buy a delicious ice cream cake at our local farm creamery! I always request that they leave it undecorated for me, so I can customize it on my own. I’ll usually use my favorite brand of natural sprinkles, and either make my own topper or find one on Etsy. This one is really similar to the one I purchased a few years ago for this event.


Pinata Time!

I found this adorable seahorse piñata and stuffed it with my favorite goodies and organic candies! Some of my go-to favorite things to include in pinatas are YumEarth Pops, Giggles, Annie’s Fruit Snacks, and Lovely Organic Chewy Candies!
DIY Mermaid Party Favors
For this party’s favors, I kept things pretty low-key, but nevertheless fun! Colorful Pom-pom pens, mermaid stampers, seashell bracelets, temporary tattoos and more organic candies!

All in all, it was a wonderful “shellebration“! With a bit of creativity and a splash of fun, you can transform any space into an underwater wonderland without breaking the bank. Let the waves of excitement wash over your child’s special day!
For more Fern party inspiration, click here!

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