I use a Samsung mobile phone. How can I adjust the sound of short messages?

According to your description, please follow the following steps to set the ringtone of SMS:

1. If you want to set the phone's built-in ringtone as SMS ringtone, please do the following:

Information-Menu Key-Notification Information Settings-Select Ringtone

2. If you want to set your downloaded ringtone as SMS ringtone, please follow the following steps:

Please create a new notification folder in the SD card, and then put the songs in this folder. After putting it away, operate: information-menu key-notification information setting-select ringtone.