Not sure if this will help at all, it’s something i’m doing in addition to the lessons above.
I chose the note “G” to start with.
1) First I located all the G notes on my fretboard, including open string notes. This number will be different depending on how many frets each ukulele has. (My uke has 16 frets, so I personally have 6 total normal places I can play the note “G” on my instrument. Two G’s per string.)
2) Going from G to A strings, I say, “G” out loud first, & play all the G’s on each string.
3) Once I can play a given note from G-A strings confidently, I go back from the A string to the G string.
I have no idea how to ‘properly’ practice this, so you’re kind of on your own with it, like me. Just shared what i’m trying since it literally covers the entire fretboard for each note.