1. Do use all six senses. If you have a mental block and are stuck writing a description, ask yourself how your six senses may react. Of course, you don't want to always include all six senses in every description, but asking yourself the questions may help the creative process. What does it smell like (pleasant or reeking)? What does it taste like (not a common sense except for food)? Are there any sounds (background noise or ominous silence)? What does it look like (colour, size, scope)? What does it feel like (texture, maybe viscosity)? What psychic impressions are felt (foreboding, delight, queasiness, etc.)? Psychic impressions (the "sixth" sense) should be used sparingly.
2. Do use present tense. There's very little reason not to use present tense when writing descriptions.
3. Do use dynamic verbs. Verbs are the workhorse of a sentence so when appropriate try to use dynamic verbs. For example:
4. Do use proper grammar. Though it should go without saying, send your mind back to Mrs. Grundy's bonehead English class and avoid run on sentences, incomplete sentences, awkward wording, etc.
5. Do ALWAYS use complete sentences. This seems like it would fall under grammar, but it is singularly important on its own. A nymph stretches out here, quietly singing to herself. Her damp hair against her body. That second sentence is a VERY common mistake in both room descs and mobile descs. It is not a complete sentence. Why? If I said to you 'Her damp hair against her body' on its own, you would have no idea what I was talking about.
Seven Simple Don'ts:
1. Don't double space between sentences. Those who have worked in an office environment tend to double space between sentences. However, what looks snappy and professional on a business letter looks awkward on a MUD.
2. Don't let Microsoft Word help you. This goes for any word processing program that has an auto-formatting feature that turns everything you type into smart quotes, automatically double spaces, changes ordinals to superscript, etc. Find this feature and turn it off.
3. Don't use "seems to" or "looks like" or "appears to be". This is a common mistake that strikes even the very best and experienced builder. Feel free to use metaphors and simile, but using the phrases "seems", "looks like", and "appears to be" weakens the impact. If the man appears to be the oldest man in the village, then chances are the man is the oldest man in the village. Ninety-nine percent of the time, it can be avoided. For example,
4. Don't reference the player in a room. Try to avoid using "you" or "your" as little as possible, preferably not at all. Generally, avoid referencing the player in the description. Instead of telling a player directly what he or she is looking at, the impact is greater and illusion less intrusive when descriptions lay before the player what is seen in the third person.
5. Don't describe objects or mobs that can be placed in the room. If the chef is in the kitchen, don't write up the chef in the room description. Rather, create a chef mob and place him in the room. Important objects should also be a separately created item, like the large monolith crackling with energy should probably be a separate object rather than merely described in the room description.
6. Don't reference history in a room. There is no way you can tell by looking at a room that it was built by an ancient group of flesh-eating wizards, known for their purple robes, who scared the natives. This is maybe the only time you can use seems: 'The hall is in shambles, covered with dust and debris of decades past. Indeed, it seems as if a war had happened here, waged on the walls itself.' if its a war-ravaged castle. You can say some things about origins, but there's a definite point of too much.
7. Don't overwrite. First, for reasons of spammy room descs. Most people don't really read the descs but skim them. You don't want to fill out every single detail down to its tile pattern, curtain texture, and the exact location of the desk, table, and three upholestered chairs; however, these little details can help beef up a sparse description for a boring hallway.