About the first two symbols,
is pronunced the same as epsylon, the only difference is the shape of lips, you have to form round lips to have that sound, the same as you do in pronuncing /o/ or /u/.
is pronunced the same as /e/, just with round lips. Just shape your lips to a round form and you'll have the sounds.
As for the nasalised vowels, try to attach a nasal sound (/n/, /m/)to the plain vowel (I do not know what keys on keyboard to push to have those signs!), and just pay attention to the change when they are adjacent to nasals, and then try to eliminate the nasal sound but keep pronuncing the same vowel. Then you'll have it. I know it is very difficult to explain how to pronunce a sound, and it is even more difficult to understand the explanation. But just continue trying, and you would eventually succeed!
This chart may comes handy, have a look: [link] , you can hear the sounds by clicking on them. Good luck,