1;just clean the outside of the window,
2; spray soapy water on the window,
3;lay down the tint clear side up and use your heat gun to shape the tint to the window,
4; when the tint is shaped clean the inside of the window and spray lightly with the soapy water.
5; peel off the clear film and stick the shaped tint to the inside
6;still using your heat gun perfect the tint.
7;job oxo

just take your time doing it and it shouldn't look too bad

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