miriam, here's my two cents...
The best way to rid of psychic vampires is send them love energy (they can't stand it and leave, over time they come less and less, until after a while they rarely ever bother you...they never completely go away --- they always try to get you when you are emotionally 'down'. Trust me, I know from experience. These thing are merely entities of conciousness that draw energy of negetive emotions. These spirit forms or not "evil" they are just a stream of energy that draw upon another source, over a period of time, they may actually realize that they can't bother you anymore and move on to someone with a lower vibrational rate.
A good excersise to try is:
While breathing in and out, concentrate your mind on your heart.
Think in your heart "I know choose tranquility and inner peace."
Then after a few moments imagine a white light surround you, or better yet imagine you are standing or sitting in a shower of golden light (the light of the pureset, tranquil emotions)... these emotions are poured down from the higher dimensions of light and enter your head when you breath in, then as you breathe out push the energy down through your body... pushing any denser energies such as blockages or negetive emotions down through your feet...
Ask your master to send energy to protect you from any negetive energy..
Once you feel all denser energy out of the body, (you will feel lighter).
Begin to breathe energy into the heart then as you exhale, imagine any blockages in your heart transform into pure love energy and harden around your aura... This will teach you two things.... 1, how to transform negetive energy into a positive energy, but also how to make a sheild of positive energy that protects you from any negetivitiy... you actually won't need to do the hand mudra after practicing this over time... I used to do the hand mudra in level 2 alot, but then I found I began to rely on it whenever I got nervous.... now I just mentally relax everywhere I go.
Any time you feel that your energy is being effected you can think "Nothing can affect MY energy". then go into a relaxed state of mind, pretend you are doing qigong and noone is watching - then whatever is trying to affect you, will leave you alone. Over time, noone will be able to affect your perfect calm state of mind.
I hope this helps my friend,
-Zakyrus