Learn how to sight sing by using the solfege Do, Re, Mi, Fa, So, La, Ti, Do and let middle C represent Do when you are sight singing working your way up and down.
Make sure you figure out what solfege to use for each beginning note before sight singing. For instance, let's say that your first note begins on E instead of middle C. Going up the solfege from Do which is middle C, C D E (Do, Re, Mi) E is Mi so you will start on Mi.
Figure out the rhythm, how many beats per measure, and what note gets the beat before you start sight singing using your solfege. Once you have figured out the rhythm and how fast the rhythm goes, then you can sing the notes using solfege to hear the rhythm through song.
Use the chromatic scale of the solfege if you are sight singing half-notes throughout your music. There are two versions of the chromatic scale the ascending chromatic scale and the descending chromatic scale. The ascending chromatic scale is do, di, re, ri, mi, fa, fi, sol, si, la, li, ti, do and the descending chromatic scale is do, ti, te, la, le, sol, se, fa, mi, me, re, ra, do.