Refer to the documentation below based on the phone manufacturer/model.

Telephone User Guides
SPA 500 Series
SPA 525G Bluetooth Headset
525G On-Demand Call Recording
SPA 302D Cordless
Off-Site Telephone User Guide

Voice Mail
Voice Mail for SPA500 Series Phones

Ring Tones
Cisco Ring Tone Options

Telephone User Guides
Poly VVX 150/250 Series
Poly VVX 300/400 Series
Poly VVX 350/450 Series
Poly VVX 500/600 Series
Poly VVX On-Demand Call Recording and Bluetooth
Poly VVX with CS500 or Savi Series Headset
USB WiFi Adapter
Off-Site Telephone User Guide

Voice Mail
Voice Mail for Poly VVX Phones

Telephone User Guides
Yealink T31P
Yealink T33G
Yealink T46U
Yealink T54W
Yealink Deskphone On-Demand Call Recording
Yealink Deskphone Bluetooth
Yealink Deskphone Headset User Guide
Yealink Deskphone WiFi
Yealink W70B
Yealink W56P and W56H
Yealink W60P and W56H
Yealink RT10
Yealink RT20
Yealink RT30

Voice Mail
Voice Mail for Yealink Deskphones