metronome.
it helps u prevent sloppiness. (if u practise right)

and the more precise u play, the more neat it is.

to play note to another note fluently.
the means of fluently means not lompat2 from one note to another note, instead u'll hear it like connected from one to another.
staccato is the contrast of it.

imagine legato as the sound of a flute.
imagine staccato as the sound of machine guns.

u use lots of hammer on and pull off. less picking for legato.