How can I go to replace my iPhone 4's screen?

See, you can also do it by yourself I have read an article about it I am putting the link below with little of the article and also I am leaving the contact details incase anyone needs their help.

IPHONE 4S SCREEN REPLACEMENT

Power off your iPhone 4S

Before performing any repair you should always power off your device before opening it up.

Remove the back plate

Using your security screwdriver, remove the 2 screws on either side of the dock connector port.

Set them aside. They are both the exact same size and length so it does not matter if you mix them up. They are interchangeable.

Gently slide up the back plate by applying a bit of pressure along the bottom with your thumbs and sliding upwards.

Now lift off the back plate and set it aside.

Remove the battery and grounding clip

Using your #00 Phillips screwdriver, remove the two screws holding the battery in place.

These screws are different lengths so make sure you remember which one goes where. The one that is slightly larger is the bottom screw.

There is a tiny grounding clip underneath the battery clip where the first screw is located. Use your spudger tool or finger to remove it before prying the clip up. Many times it can go flying if you don’t remove it first and then you’ll have difficulty locating it so it’s best to remove it first.

Now use your spudger tool and at the bottom of the battery clip, gently pry upwards so the clip pops up. If you lost data after you updated to a new iPhone, you can always use Gihosoft iPhone Data Recovery to get the data back from the old iPhone or backup.You may also like: iphonerecovery.com

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Move to the edge of the iPhone where the volume buttons are located and use your spudger tool to carefully pry up the battery. It is stuck down with a good amount of adhesive so be careful when prying upwards that you don’t bend the battery. This is why I do not use the plastic tab that is provided. It typically rips or bends the battery. If one part is resistant move your pry tool a little further down and gently start prying it up in different places taking care not to come too close to the volume button cables towards the top.

Once you’ve gotten the battery pulled out of the iPhone 4S we can move on to inserting the replacement battery. READ MORE