What is the right way to install an update?

[maninder4x4]

Should i reset my Lumia phone before installing update..i had two lumua 520 phones...but after installing black update on both made them battery hungry...help me guys

 

[Guytronic]

Soft reset first.
Hold on and volume - together for 10 seconds.

 

[maninder4x4]

Soft reset ...what about factory reset......

 

[Guytronic]

The factory reset can fix most odd issues.
For many with depleted battery time after updating the factory reset has worked for them.

I've factory reset my 521 and 925 a few times in the last couple of months because of a few things that happened with the developer preview.