1. Open an image in PSE Editor.
2. Make a selection of the object to which you want to add glow. I used quick selection tool from the left toolbar for making this selection.
3. Once the selection is made, right click on the selection, and choose "Layer via Copy"
4. A new layer gets created as shown in the image below after performing step 3.
5. Go to Layers menu>Layer Style>Style Settings.
6. Add Outer Glow by checking "Glow" and selecting an appropriate color from the color picker. You may adjust the size and distance of the effect. Also you can add drop shadow effect if it suits your needs.
Here are my initial and final images :