how to make circles in particle system

I'm trying to make my particles circles but they're squares, how can i fix this

 

In the Particle System, under the Renderer section, make sure you have a material assigned to the Material field. That material should be one that supports alpha transparency and has an appropriate texture assigned to it.

Try creating a brand new Particle System and checking out the configuration of that to see how it should be done to create circular particles.

 

This is remarkably unhelpful.

 

Still having the same problem months after uploading your question? Just to give an answer to the thread I came to when searching for my own answer, here are the steps to have smooth circle particles instead of square particles.
1. Create a new material for your particle
2. At the top of the inspector for your material, choose the particles/unlit shader
3. Set the rendering mode to fade
4. to the left of albedo under maps, click the little target circle thing.
5. Search for Default-Particle
6. Configure the albedo color with the intensity you desire.
7. Read books about manners so that you are less rude on the internet

 

XD
Thank you so much, just what I needed