2. Select the Type tool from the toolbox. The text creates its own layer, you don't need to add new layer for the text. And in the Text setting I used this format:

3. Because I will going to use a white matte for the text so, it's better for me to change my background color for easy formatting. Select the Background Layer and choose other color for background.

4. Then go back to Text Layer. Active it and click the Add Layer Style button at the bottom of the Layer palette and choose stroke. 

5. And set the following setting for stroke:

6. Add shadow. This is very important to looks the sticker real.

7. So here is the final result with the other sticker text I made using the same Layer style:

Start making your own too. You can use this style in any text or even your images can be looked so great too with this sticker style. Happy reading!