What order do I watch the Tenchi anime in? I'm trying to watch the anime series Tenchi and don't know what order to watch the episodes in, including the OVAs and movies. What order are they intended to be watched in?
Theres are allot of story pieces involved. But one of the easyest ways to decide in which order to watch would be by checking out this website. It has the storys and their time settings layed down in detail (this might be a good addition to the How are tenchi timelines related) 

For a casual viewing order you should watch it in this order


Tenchi Muyou! Ryououki (1992-1993)
Tenchi Muyou! Ryououki Omatsuri Zen `y.... (1993)
Tenchi Muyou! Ryououki (1994)
Tenchi Muyou! Ryououki (2003)


Then you can follow this up by the side story about his parents


Tenchi Muyou! Bangaihen: Galaxy Police (1994)
Mahou Shoujo Pretty Sammy (1995- 1997)


And from here on out you can either go check out alternative settings


Shin Tenchi Muyou! (1997)
Tenchi Muyou! Manatsu no Eve (1997)
Tenchi Muyou! (1995)


Or even the alternative version of  the side story


Mahou Shoujo Pretty sammy (1996)


And the alternative version settings variant of this


Sasami: Mahou Shoujo Club (2006)
Sasami: Mahou Shoujo Club 2 (2006-2007)


And finally you can check out the Same setting story


Tenchi Muyou! GXP (2002)
Isekai no Seikishi Monogatari ( 2009-2010)
Dual! Parallel Runrun Monogatari


With this info it is pretty much up to yourself how to actually watch it. But for story purposes I would advice at least watching the first 4 I stated in that order.