i know what you mean about having a lack of time,i struggle as im a busy guy too.but it isnt really that hard to find half an hour in the day,i guess it just depends on privacy and how much you really want it.
i usually find that i do my excercises at night before bed,and kinda mix it in with my usual routine so it doesnt actually take much time out my schedual.
seeing as you need to have a good wash after jelquing to get rid of the lube,an i usually have a bath before bed most nights anyway,i jelque for around 10-15 mins(shud be more i know,but im workin on it!)while the bath is running,when i wud be doin nothing anyway otherwise. this way im only actually using about 5-10 mins out my day.i then bath an wash of lube etc,and i find it easier to get to sleep watching tv in bed.so while i watch tv i do my stretches.plus,because its late,i have privacy too.
i know this mite not work for everyone,but just giving you an idea that it doesnt need to completely eat into ya day.
good luck mate