when you have done the above,
try singing the major scale with a seventh note[te] flattened [mixolydian mode],check it against a musical instrument,then flatten the [me] note as well as the [te] note[dorian mode], check against an instrument.
next practise, do me so do[arpeggios], and then descending ,then me so [do high],and descending, check with an instrument.
then sing the major scale staccato[short and stotty].
then practise it making different vowel sounds oo,a,e,i,o.listen to yourself singing songs with p and b,d and t,and s,for sibelence and clarity.