UPDATE UPDATE UPDATE:
MK Glow Free is no longer available at the Asset Store. (You can still use the paid version though)

In Unity 2020 it’s much more easy to use the glow/bloom effect. Just follow this tutorial:
https://www.youtube.com/watch?v=6SKHDaSe768

In this tutorial we’ll create the awesome glow effect in both 2D and 3D. Download the Free MK Glow tool from the asset store. Follow the link below.


♥ Subscribe to Oxmond Tutorials. Stay tuned!
https://bit.ly/SubscribeOxmondTutorials

Download MK Glow here:
https://assetstore.unity.com/packages/vfx/shaders/fullscreen-camera-effects/mk-glow-90204?aid=1100l4p9k

Download MK Glow Free here (DEPRICATED):
https://assetstore.unity.com/packages/vfx/shaders/fullscreen-camera-effects/mk-glow-free-28044?aid=1100l4p9k

Download the X bitmap here:
https://oxmond.com/download/tutorials/unity/oxmond_x_bw.png

Free Assets from the Unity Assets Store:
https://assetstore.unity.com/lists/top-free-packages-13201?aid=1100l4p9k