Austen, unlike her contemporaries of the Romantic movement, actually prefers not spend a great deal of time describing either setting or characters. As far as descriptions go, she only says what is absolutely necessary for the story line and then allows the story to speak for itself.
We know that overall the novel is set in the town of Hertfordshire in which the Bennets, the Lucases, and Mr. Bingley reside. We also know that the novel is specifically set in the village of Longbourn of the town Hertfordshire in which the Bennets' Longbourn estate presides. We learn the name of the town in the third chapter when, after Mr. Bingley is invited to dine at Longbourn for the first time, he must cancel to go to London. Mrs. Bennet cannot "imagine what business he could have in town so soon after his arrival in Hertfordshire" (Ch. 3). We later learn the name of their village and estate when, after the ball in Meryton, Austen describes them as returning in "good spirits to Longbourn, the village where they lived, and of which they are the principal inhabitants" (Ch. 3).
The one setting that is described for us in some detail is Pemberley, Mr. Darcy's estate. We know that the park consists of beautiful woods leading to the estate. We also know that the road leads into a valley in the park and on the opposite side of the valley stands Pemberley. The road then winds around the valley towards Pemberley. We also know that a natural stream runs in front of Pemberley. Austen also takes time to describe the outside of the building, something she never usually does:
It was a large, handsome, stone building, standing well on rising ground, and backed by a ridge of high woody hills. (Vol.3, Ch. 43)
However, describing the setting of Pemberley is important to Austen because she uses the book to say quite a lot about class distinctions and barriers. Austen is pointing out that class distinctions are a ridiculous part of society and intentionally has a gentlewoman with working class relations become the mistress of Pemberley, which is owned by a gentleman with noble relations, thereby breaking down at least one class barrier.
You could use quotes along the lines of "A single man of large fortune; four or five thousand a year" - (Mrs Bennet when talking about Bingley to Mr Bennet) to show the culture, as four thousand a year is absolutely nothing by today's standards. Also, furthering tht quote, you could use the nature in which Mrs Bennet thinks only of her daughters marrying such a wealthy man to show the different attitudes of that era towards marriage.
There are several indications as to place, you just need to find one that suits your information.
As for time, you could use a series of quotes that highlight activities and attitudes specific to the 1800s (e.g. the balls at various houses).
Characterisation could be linked with conflict. Using quotes such as " In spite of her deeply-rooted dislike, she could not be insensible to the compliment of such a man's affection...etc. etc." - (Elizabeth Bennet when Mr Darcy has just confessed his love for her the first time) show not only the conflict (i.e. Darcy's unreturned love for Elizabeth) but also Elizabeth's character in the way she feels pity but is strong and independent.
In addition, quotes from various places throughout the book where Elizabeth meets Darcy and gives an opinion of him (gradually more loving) could symbolise not only her character, but also his in the way he appears to others. (E.g. when Darcy is at the first ball "His character was decided. He was the proudest, most disagreeable man in the world...")
I hope that kind of gets you on the right track :)