Here's how you can add cool effects and textures to your designs to give them the perfect finish you are looking for:
Decide what effect you would like to work with based on the tones and type of images. Let's look at dirt, as I would like to texturize the background of my image.
Once you are happy with your selection, add it to your canvas.
Here's what I went for -
Scale the effect according to your preference. You can also make adjustments to the appearance on the right panel of your screen.
And we are done!