When designing, the way you save your work is one of the most important things to consider, as it can affect the quality of your design. This is especially vital in attracting clients – people will not be enthusiastic about a blurry, pixelated image.
One step I always take before saving my work is slightly sharpening the whole image. To do this, firstly create a layer of your whole image. Press Ctrl+A (select all), Ctrl+Shft+C (copy merged), Ctrl+D (deselect) and the Ctrl+V (paste). You should then have a merged layer as shown.
Now we can sharpen the merged layer. Go to Filter > Sharpen > Smart Sharpen which should open the Smart Sharpen dialog box. The settings you use here are up to you, but I usually use an Amount of 500%, a Radius of 0.3px and Remove Gaussian Blur. Any other settings I would leave as default. These settings should give your image a slight sharpen without it being too noticable. Feel free to try different settings to see what works best for you.
Now that we have optimised our image, we can now save it. I recommend going to File > Save For Web. The best preset to use is usually PNG-24, as shown. All other settings can usually be left as default, but if you need a smaller image size, you can change Image Size Percent to a value smaller than 100%. Then you can press Save, choose your file name and file destination.
This is generally the way I save my images. If you have any other tips, or have a question, leave a comment on the post! Hopefully you found this helpful.