help with proportions

[loud plover]

I can't seem to get the top of the water bottle right

[agile hornet]

HI! I would recommend trying to do a couple blind contour drawings. Basically, you'll want to draw your object without looking at your paper (though peeking won't hurt you too much) and trying to to not lift your pencil. This can help with hand eye coordination and forces you to look at the object you're drawing. You'll want to draw what you see and not what your brain is telling you the object should look like.

additionally, breaking down objects into simple shapes like squares and rectangles should help. Pay close attention to how big these shapes are compared to one another. You could probably break the bottle down into one long rectangle with a square on top.