Description is one of those love-it-or-hate-it things. Some readers want more, more, more; they want to see every button and bead on the dress, every scratch on the woodwork. Other people roll their eyes and complain about slowing down the story when they run across long passages of descriptive infodump. Still others want to have their cake and eat it, too–they want to know what everything looks like, but they don’t want to stop and wade through two pages of scene-setting every time the characters go somewhere new.
The writer can’t please everyone, but there are a couple of different things one can try, depending on one’s personal style and on the viewpoint of the story. One can, of course, go ahead and do the two page descriptive infodump. If done well, this will please some readers enormously, like the ones who adore Eddison’s The Worm Ourouboros. Other readers will sniff and give the story a pass.
A related technique is to use short descriptive paragraphs every time a new character arrives or the POV character enters a new place: “Harvey looked at the cottage. The thatched roof was uneven and rotting; mice had clearly made homes in it. The door hung crookedly on rusty hinges, and the stone flags in front of it were cracked and half buried in mud. As he watched, a crow flew out of one of the empty windows. Sighing, he started toward the door.”
This amounts to a mini-infodump. It provides a description without stopping the story for long…but it does still stop the forward flow of the story, at least most of the time. If you’re writing an omniscient viewpoint, the mini-description often works fine. In tight-third and first person, it works best if your POV character is the sort to stop and take stock of every new place (and it helps if you intercut occasional character monolog/internal dialog/reactions, to remind us that this is the POV’s description, such as: ”The stone flag was cracked and half buried in mud; he would have to be careful not to trip when he got to it.”)
A somewhat different approach is to give the description as part of the action, as the character experiences it through his senses: “Harvey started toward the cottage. His feet squished ankle-deep into the soft mud around it, and when he finally reached the stone flag that served as a doorstop, its two halves wobbled underfoot. The rusty door hinges had bent under the weight they held; it took all his strength and several minutes to wrestle the door open. Bits of half-rotted thatch dribbled onto his head as he worked, and his efforts startled a crow that had been hiding somewhere inside. As it flew out an empty window, cawing reproachfully, the door gave way at last. Why me? he thought, and went inside.”
This gets in a lot of the same descriptive details as the mini-infodump, but because Harvey is moving forward and doing things, the story doesn’t stop while the reader gets the description. This technique works really well in both omniscient and tight-third; in first-person, it depends on the POV narrator’s voice. Again, it helps to intercut the occasional POV reaction or internal comment…but only occasionally. The more reaction you put in, the more psychological importance or weight the description has and the more convinced the reader will be that this place (or that rusty door hinge) is going to be vitally important somewhere. If it turns out not to be, it throws the reader off.
Sometimes, especially if there are several characters in a scene, you can give the basic setting in a line or so and then add details both in dialog and as the characters act and experience the setting: “As Harvey and Jane approached the ruined cottage, Jane shook her head. ‘Looks creepy,” she said. / ‘It’s just old,’ Harvey told her in an unconvincing tone. / They started for the door, their feet sinking ankle-deep in the soft mud. ‘Watch your step; the flagstone is cracked,’ Harvey said. / Something rustled, and Jane jumped. ‘What was that?’ / ‘Mice in the thatch.’ Harvey studied the door with misgiving. The hinges had rusted, and it hung crookedly. An experimental tug confirmed that it was jammed in place. ‘Give me a hand with this.’”
In all cases, the thing to focus on are the details, the critical bits, the one or two things that make this cottage/castle/bar different from every other cottage/castle/bar, or the one or two things that the POV character would especially notice. A bard, entering the bar, might well notice the worn carving of a harp on the end of the bar table, while a mercenary, entering the same bar, might be more taken with the oddly shaped sword hanging on the far wall. Neither one would be likely to comment on the wooden rafters or the beer kegs, unless there were something unusual about them. Of course, if you are writing in first person and your narrator happens to be the oblivious sort who really doesn’t notice anything…you’re up a creek.
Also note that the more the description is sandwiched in among dialog and character action, the longer the passage gets. For a short, not-terribly-important scene, you may want to use a mini-infodump-summary in order to keep things short. And, as always, variation is good; if you always use the same techniques to provide descriptive details, sooner or later your readers will start noticing. Finally, using sensory cues other than visual ones (sounds, smells, textures/sensations/feeling, taste) can add a lot-things like the soft mud and the flagstone wobbling underfoot, or the sounds of the mice and the crow.