How to Entering recovery mode on Your phone

This is possible to enter recovery mode by pressing some button combination during boot sequence of the device. The key combination differ from phone to phone, but manufactures usually has similar invocations for similar phones. You have to read a page with instruction for your phone to make sure that you are not doing something weird. When these keys are pressed, the device does not perform normal boot sequence. Instead of this, another partition is picked and kernel+recovery_apps is invoked from this recovery partition, so the rest of the flash is untouched (see custom recovery_apps list above). The combination of pressed keys has nothing to do with the recovery kernel+recovery_apps (ie. what is flashed to the recovery partition, this will be run). Sometimes there is no recovery flashed, so even keys are pressed, no recovery mode is invoked. You may still be able to flash own recovery to the device by Odin mode and use it later.

Example :

Source : XDA