Pre-charging the mind with desired subject matter. To be effective, this should take a solid month of prep.
For earthy experience....spend a month camping. No gadgets, nothing ditital, eath simple food, wear simple clothes, stay dirty.
Mythological/ancient experience...spend weeks studying mythology, hanging out with others of similiar interest, surround yourself with artifacts relevent to the chosen mythology.
Ect.
This works (results will vary!) for any chosen subject: study the subject, think about it, surround youself with relevent objects. We all do this all the time: we always direct the experience in this regard, though subconsciously, accidentally, sometimes clumsily.
About the solid month prep for this method...well, if we do this subconsciously all the time then: live the trip you wish to have. I keep opening my eyes lately when in hyperspace--something new for me--and I keep seeing how my phsysical space could be made better. I need do some cleaning and decorating and landscaping bfore I blast off again.
"Living the trip you wish to have" means also keeping a stimulating life. Move around, change habbits, new scenery, ect--who wants to have the same type of trip all the time?