Literally only a handful of squares can be filled in without guessing.

Some guessing required. But possible with some artistic drawing...

Hints?

You've 2 stars centred on r18/c3 & c23.
The base is a symmetrical U shape with the 5 touching the sides.

For the head start in the top corners a work down to form the outline of the head.
Mouth should fall into place from there.
The nose is 5 dots forming a v.
The eyes start in c5/r5 & c20/r5 and angle into the centre.
You then have 2 eyebrows & a widows peak at the top.

Teesea, I thought I got it with you hint, but it says "Invalid answer"!!

THe eyes start in row 6 not 5.

Tried three different variants, all invalid. I think I got the outline and the mouth from the hints, but the eyes and eyebrows completly elude me.

Total piece of cr*p.
After MANY failed attempts - finally there.
So spoilers:
EYEBROWS - R2C5, then stepping down and inwards. Symmetrical.
EYES - 3 down starts on R6C5 as does 2 across, then stepping down and inwards like eyebrows.
NOSE - downwards pointing 'V' with bottom at R15C13 and consisting of 5 points
MOUTH - 6 across starts at R18C10, 5 across starts at R20C11
FACE - 5 down on left starts at R13C12. There is a 2x2 square R13,14 C6,7 and C19,20
Good luck!

Slight edit - eyes upper corners start in R6 C6 and C20.

Even the hints are rubbish - there is no '5' in column 12 etc. I give up.

Finally did it with hints and a lot of guesswork.

DONE!! Holy chirst. Thanks all for the tips. Still required a good amount of guesswork.