Some of the meds I take make me drowsy and I know how this can be a nuisance. I'm not familiar with clonidine or how you take it, so I'm not much help here, but if I have something going on which requires being fully alert, I try my best to wait to take the med until I'm at home and hopefully later in the day.
I have become used to a couple of the meds and can tolerate them better than I did at first.
9 times outta 10, I end up falling asleep during a movie me and my husband are watching. .....not such a fun date

I also notice that if I have eaten, I tend to get sleepier easier when I take the drousy meds.
Drinking a fizzy soda sometimes helps as a 'kicker'.

Rae