A mnemonic is to imagine u with two dots, one at each top end of the vertical parts. The dots move down and to the left as the letter straightens, with the tops of the vertical parts becoming the left and right ends of a bar, forming ●● ▬.
Here is practice:
●● ▬ g l y
●● ▬ p ● ▬ ▬ ● ▬ r ▬ ●●
●●●● ▬ ▬ ▬ ●● ▬ ●●● ● ▬ ●●● ▬ ▬ ▬ ● ▬ ▬
k ●● ● ▬ k ● ▬ ● ▬ ▬ ▬ ▬ ▬ ▬ ●● ▬
c ▬ ▬ ▬ ▬ ● ▬ ●● ▬ ● ●● ▬ ●● ▬ ▬ ▬