There are many different exercises you can do. There are alot of websites and books from which to get them from. Remember that for any exercise you do that involves another person that you may be picking up on their thoughts (telepathy) and that you may not be sensing the psi balls, using psychometry to see what is in the envelope and etc...
You can do this one with or without a partner. I would suggest with, because you can take turns changing the colours, emotions, shapes etc and guessing at what it is. Sit comfortably, Id suggest lighting some candles and turning off excessively bright lights and also turn off/avoid anything distracting. Sit facing your partner and place your hands as if holding a ball between you and your partner, try having one person hold the top and one the bottom. Now you both focus on creating a ball of energy between your hands. Imagine the energy flowing from your hands. Your hands may start to tingle, or grow hot; this usually means that there is some energy there and that your psiball is taking form or is there. Try and sit and perceive the ball, look through your fingers, generally they look almost like a mist, or an oil spill. They are often moving and they vibrate. When you are both ready and comfortable try changing the ball into colours/emotions etc. And have the other person guess at what it is. When you are done, you can either leave the ball to dissipate on its own or take it into yourself. Write down how well you did at perceiving, and how you perceived it. Keep track of how many you felt correctly and also which ones gave you trouble.
A fun but challenging exercise to do. Get a friend to take a variety of objects that you havenít seen before. Things like jewellery, photographs, business cards, etc (you can even use pieces of fabrics. really anything goes). Have them put these items into separate envelopes and number them. When this is done try and figure out one by one, what is in each envelope. Use energy to try and feel what it is, what the characteristics of it may be. Imagine feeling it, seeing it, smelling it. Try and use all emotions as well as intuition and first impressions. Write them down. It isnít necessarily about getting exactly right what is inside. Write down colours, feelings, anything that you sense from it. Spend aprox. 30 seconds or so on each envelope. Once you have gone through them all open them up and see how you did. See how many different characteristics you picked up. Feelings that may be expressed from it. Ask your friend what they feel when they think or see these items, as emotion may have been placed on them that may not necessarily be obvious to you.
For psychometry: guessing cards (using playing cards, but try tarot or other divitination decks for a variety), guess what's in peopleís wallets or pockets, trying to read letters or mail before you open them, have a friend draw a picture or shape and then try and guess what it is, this can also be used for developing telepathy.
For telepathy: guess what number, colour or shape a friend is thinking of, guessing what the person you are talking to will say next.
Exercises for Everday Life
When at a store or working in a store, try and guess what people will buy, or how they will pay for it (credit card, debit, what size bills etc)
When talking to people try and guess what they will say next or what they are thinking of.
Try and read peopleís energy, try different ways to sense it, colours, textures, shapes etc.