Top G is easy: all finger down except 3rd finger LH, ie play a clarion D and lift your 3rd finger off.
For a smooth transition from low E to here, sorry, you're on your own!

Practise...etc
The high G# has a lot of alternate fingerings. Some work better with some clarinets than others.
The fingering chart is here:
http://www.wfg.woodwind.org/clarinet/Good luck.
Oh, and when practising those upper altissimo notes, best do it in a field far from any built up areas!
Steve