How to take, make, or save screenshots on Oppo devices

Oppo Mirror 5 Lite Oppo Mirror 5 Lite
Oppo R7 Plus High Version Oppo R7 Plus High Version
Oppo F1 ICC WT20 Oppo F1 ICC WT20
Oppo R9 Oppo R9
Oppo A37 Octa Core Oppo A37 Octa Core
Oppo A59S Oppo A59S
Oppo A39 Oppo A39
Oppo A77 SD625 Oppo A77 SD625
Oppo R9S Pro Oppo R9S Pro
Oppo A79 Oppo A79
Oppo A75 Oppo A75
Oppo A75s Oppo A75s
Oppo A73 Oppo A73
Oppo A85 Oppo A85
Oppo R15 Dream Mirror Oppo R15 Dream Mirror
Oppo A83 Pro Oppo A83 Pro
Oppo A73s Oppo A73s
Oppo F9 Oppo F9
Oppo F9 Pro Oppo F9 Pro
Oppo R17 Pro Oppo R17 Pro