I can see how you'd do an especially I I. You just need to include the serifs, which I always do in handwriting anyway.

But how do you emphasize a lowercase 'l'? The only method I know is to make it cursive, which looks terrible.

(I don't really need to distinguish l from I, because I put serifs on I. But I do sometimes need to distinguish it from 1; in natural writing, 1 and l are identical.)

You can generally just add a little rightward hook at the base. (Which is what the Ubuntu font above does)