STEP 1 :

Insert sim in phone
Go to Settings
Select Connect

STEP 2 :

Select [Cellular networks]

STEP 3 :

Select [Access Point]

STEP 4 :

Select [Add] to create a new APN: Either [+] or [...]

STEP 5:

Enter configuration information

◦ Name (name): skymobile
◦ APN: mvno.net
◦ Username: skysim
◦ Password: sky

*Note:
All letters are lowercase

STEP 6:

Select profile [skymobile]

STEP 7:

Enable [Cellular Data] mode