[quote=@Gendarme][list]
[*]How do I do a proper collaboration post?
[*]How do I portray ships, buildings, and inanimate objects in general through writing without sounding boring?
[*]What is the right amount of detail in most posts? Are there any exceptions?
[*]I intend to head to an Advanced role-play at some point, but I would like to increase my skill beforehand. Do you have any general writing tips?
[*]In addition, what early signs are there that a role-play will have longevity and not die out quickly? How can I help keep a role-play alive and fun as a poster?
[/list]
[/quote]

Hmm... A lot of this has been covered earlier. We'll try not to cover those parts again.

#1: Collabs.
There are many solutions for this. What is right of those methods is subjective. But ideal for collabs is having participating characters and players understand each other at least somewhat. If you understand how your partners' characters work, then it is easy to determine roughly how they'll react and tailor your actions to fit with it.

If you're writing a fighting collab, we feel it is important for the characters not to invulnerable (unless the situation calls for it). Though an expert might be fairly guaranteed to defeat a journeyman in combat, it is not guaranteed that he'll come out of it unscathed. behave how your character would have behaved. 

#2: portrayal.
How would your character see it? would (s)he understand what it is, or how it works? if you've got a marauding barbarian, (s)he probably wouldn't care overmuch for calligraphy. Would (s)he care about the sight?

#3: detail.
THe level of detail is subjective for each post/RP.

#4: Advanced.
Read stuff. books. RPs. Anything with the sort of lingual quality you desire. 
Don't be afraid to ask questions. Most GMs are helpful.
don't be afraid to jump in the deep end. 

tight-knit group that doesn't die after the first dry-spell.