The Gram-Schmidt process is a means for converting a set of linearly independent vectors into a set of orthonormal vectors. If the set of vectors spans the ambient vector space, then this produces an orthonormal basis for the vector space.
The Gram-Schmidt process is a recursive procedure. After the first

vectors have been converted into

orthonormal vectors, the difference between the

original vector and its projection onto the space spanned by the first

orthonormal vectors is normalized to obtain the

vector in the orthonormal collection.
In two dimensions, start with a vector

and normalize it to obtain

. Next, project

onto

and compute

, the difference between

and this projection. Finally, normalize this vector to obtain

.