Well... first of all, im much of what Don Juan calls a "lyric sorcerer", meaning one who knows much theory and few practice... im too lazy and unmotivated to follow anything seriously, and thats why i never had many success with meditation and such.

Anyway... my 1st technique i learned when was 15, and it was called "autogen training"... the idea of the book it was achieve acid-like effects using just the mind. That was the first time i read about any relationships between psychedelics and meditation... so i think i can say that it was the beggining of my journey.

The first step was lay down, or sit in a confortable position. (i, lazy as i am, always lay down... and almost always fall in sleep...)
Then breathe deeply and concentrate in the weight of the body. Try to imaginate the body submerging in the couch, or melting, or anything which makes you aware of its weight.
In the start, keep repeating formulaes like "my right arm is heavy... my right leg is heavy... my left arm is heavy..." helps to feel the weight.

After mastering the feeling of body weight, when you can feel your body like a heavy mass of jelly, the next step is concentrate in the feeling of warmness in the whole body.
Formulaes like "my right arm is warm..." and so may help the begginers.
When mastered, those 2 techniques works wonders in matter of relaxing. The body feels like if you were in a warm bath, floating... its very pleasurable... and if done during 15-20 minutes can provide a very effective rest. I used to do this, and after this 20 minutes i would feel like i had slept several hours, and awoke well refreshed and disposed.

Note that after doing this relaxation, its not good just jump up from the couch... even because sometimes its almost impossible. The body is very relaxed, and it needs to become used to tension again. So, when you finish the relaxation, you must "re-awake" the body very slowly. Move the fingers of one hand, open and close them. You will notice that there is a need of great effort for doing so, it seems you became weaker... then, after it, move your hand, slowly. Then, slowly, move the arms, then the toes, feets, legs, neck and head. After it, its very good and pleasurable to stretch all the body... i think its what most resembles the feeling of had slept a lot.

If this exercises were done for more time (30min-1h), the final effect is much like a indica stone. When you finish, you feel very slow, peaceful, happy, and so... in fact, the first time ever i did use weed (ate some raw weed), i described the effects i had (a light body stone) as "the same of 2 hours of relaxing".

But that are only the two inicial steps. After being deeply relaxed, heavy and warm, you must concentrate in the breath. Try to feel the breath, and forget anything else. You must be all breath, and nothing else.
Again, formulaes like "im all breath..." may help.
When mastered, you feel like the breath is the only thing that exists... its hard to describe, but its very pleasant also.

After mastering the awareness of breath, you must concentrate in the heartbeat. When you were breathing calmly and relaxed, focus your awareness on your heart beating. Feel the beats of it. Feel them propagating throught all the body. It was an interesting feeling... i could actually feel the heart beat, and then the wave generated by it run through my body, i could feel the beat going down to my legs until the toes, going down to my arms until my fingers, and going up until the head... it was weird, but very nice.

That 4 techniques were the only i actually mastered. For me, the pleasurable feeling i got with them were enough, at that time, so i never went further with this techniques. Anyway, the next steps are:

Concentrate in a heat coming from the solar plexus. Try to feel it like if there was a small ball of fire in it, which radiates heat for all the abdomen.

Next, you must feel your forehead confortably cool. Again, it is accomplished by imagining the feeling of coolness in the forehead.

An interesting use for this relaxation techniques is somewhat caled "positive thinking", "self-hipnosis" and such. The idea is keep repeatedly a thought into the mind while the body is relaxed during the practice. Like, after feeling your breath, heart, heat in the plexus and cool in the forehead, concentrate in a thought like "i will achieve good grades", or "i will stop smoking cigarretes", or anything you wish. If repeated enough while the mind is relaxed, it can have amazing results.

Anyway, this are the body techniques. The next step are the mind techniques.

After having you body relaxed and having accomplished everything above, you must visualize some color. You must see a color with your eyes closed. I really dont know how, as i never mastered it and am a very poor visualizator. Im only translating the book, but im sure lots of peopls can do this, after enough training.
The eyes must be looking to the "third eye", a point in the forehead somewhat above the between the eyes. When mastered this technique, the people must be able to see a uniform field of a color in front of the closed eyes. The author call the color you see as "personal color". It says that is not a previously choosen color, but rather the color you see when the eyes are closed. (I see black , as my eyes are closed , but as i said, im not a good visualizator.)

Mastered this technique, you must visualize any color you wish, at your choice. Choose the color, relax the body with the techniques, and then visualize the choosen color.

Next step is to visualize concrete objects. After relaxing and visualizing colors, you must try to visualize an object. Anything. You must practice it until you actually "see" the object as if you were looking at it.

After visualizing concrete objects, the next step is visualizing abstract things, like "justice", "happiness", and such. The book says that after mastering this, many people feels like tripping... they see things, or hear things, or whatever...

The book continues, and the next step is visualizing some feeling. You must concentrate in the feeling that comes to your mind, and visualize it.

Mastered it, you must visualize a choosen person. It helps to visualize persons that you have not stong feeling toward they, as this feelings usually hinders the visualization. When mastered, this technique allows to feel what are our real feelings towards the people visualizated.

And, at last, you may use it to ask questions to your inner mind. After mastering all the prevoius techniques, you may be able to ask a question while your mind is in this "alterated state", and watch what are the responses.

Well... after almost one hour of heavy translating/typing, i discovered a site that covers all the body techniques i described above... If i knew it, it would have saved me a lot of time... anyway, the explanations there are more detailed, so the link is:

Autogenics -- A self-help training schedule

Well... later i will post the another techniques ive tried... even cause its the longest post i ever wrote.