Tuning Guitar

 There are basically three ways to tune a Guitar:

1. By Ear 

- For this to work, either you will have to know the sixth string in the E note, or get a piano or a tuner to tune that string. 

- After sixth string is tuned, put your index finger in its 5th fret and you will have 5th string's note. 

- Do that till 4th string, but in the 3rd string, put your finger in the 4th fret in stead of 5th fret. After that you will have your 2nd string's note. 

- Use 5th fret for the last string too.

2. Piano 

6th - E

5th- A

4th- D

3rd- G

2nd- B

1st- E (after Middle C)

3. Tuner Apps

Download a Tuner app and tune your Guitar 

The best one would be 

https://play.google.com/store/apps/details?id=com.GuitarTunerEasyFull.Chords

 Others are there too

https://play.google.com/store/apps/details?id=pl.netigen.simpleguitartuner

https://play.google.com/store/apps/details?id=com.megaj.guitartuner