If you don't have anything particularly important you need to wake up for the next morning, stay awake longer to get into a sleepier mood. If you can find that perfect point, LD's and recall come extremely easy.

I tend to have this issue too, so sometimes when the sleepy mood doesn't work, I just imagine putting all my worries into a little box at my bedside to be dealt with later. A little pre-sleep meditation does wonders too.