The steps are as follows:

1. First, you need to click the "Video Editing" function on the homepage of "Refreshing Video Editor" to enter the video import page.

2. Click the "+" on the video to add the required video. After the video is added, click "Next" to import the video to the video editing page.

3. In the video editing page, find the "Sound" module, and then click the "Soundtrack" function in the sound module.

4. In the video soundtrack page, click "Local" to select music from your phone for soundtrack, and click to complete the addition.

5. You can also add the soundtrack that comes with the software by clicking on items such as: Trendy Play, Discovery, Memories, Street Travel, etc. After the music is added, adjust the yellow punctuation point on the horizontal line to control the volume of the soundtrack. After setting, click "√" in the lower right corner to return to the video editing page.

6. Click "Save Draft" on the video editing page to save the video to the draft box, and click "Publish" to share the video with friends.