Every experience you build in Minecraft gets better when there are particles and effects to accentuate the action. Minecraft: Bedrock Edition supports a concept of particles - lightweight visual items that you can design - as well as particle emitters - logic for determining when particles are created. You can add these particles to your resource packs and then use them in experiences with the particle command and as a part of your JSON definitions.
One tool for visually editing the particle files that underlie these is Snowstorm - an app by JannisX11, who also created Blockbench.
You can access Snowstorm as a web appliation via https://snowstorm.app or as a Visual Studio Code plugin. A Quick Setup tab within Snowstorm makes it easy to get started with various pre-set motions and appearances.
Important
Snowstorm is provided by external, third-party contributors and is not a Mojang/Microsoft offering. Users should use at their own discretion.
To see how you can use Snowstorm to build particle effects, visit this tutorial.