My experience has been of getting clear impressions and either being shown things symbolically or hearing voices.
I have not been able to manifest anything physically though.
It seems to be quite a clear thing, one day you cannot do it and the next it happens as though you have been doing it for all of your life.
It is sometimes hard to know when hearing if it is your mind or the voice of the summoned entity, however, it is generally the first impressions and sounds that are theirs, before your own mind interferes with it all.
Don't worry if you just get one very loud word at times, that may be all that you will get and I would not consider it a failure on your part as a beginner.
Another thing is that if you don't practice for some months, you can 'lose' some of your ability, or at least, that is my own finding.
Also, if what you hear doesn't make sense, write it down because later on, say in a few weeks or months time, it is likely to be very clear what was being said at that time as it will have either come true or you will find it in a book or something.
Most of all, enjoy it (IMG:
style_emoticons/default/wizard.gif)