When I first decided to 'have a go' at genealogy (about a year ago), I decided that I would research my father's family. I didn't know anything about them, only my father's birthdate and the year of my parent's marriage. You really don't need much to get started. I sent off for my father's birth and marriage certificates, from those I got the names of his parents, (my grandparents).
The next step was to send off for the birth and marriage certificates of my grandfather, to get the names of his parents, (my greatgrandparents). Now we were getting somewhere, so I decided not to rush back in time any more, but to concentrate, and expand on, what I had already found out.

I now knew that my family came from Oxford, and that my greatgrandfather, George Jeffery, had married Harriett Kimberley, from Little Milton, in Oxfordshire. They were married in 1858 in Headington, Oxfordshire.
Now that I knew the date of their marriage, I could start looking for them in the censuses. As they were married in 1858, the next census would be the one in 1861. You can get an awful lot of information from each census. I found out that George was a Whitesmith, he was 29, Harriett was 27, and they were living in 35, Albert Street, St. Ebbe, Oxford. The census also showed their first child, William, aged 1yr. All these details from just one census, you can begin to feel the family come to life. Here was a young couple, living together in their first home with their young son.
The next census we can look at is for 1871. Let's see what has taken place during the last 10 years.
1871 census at Sidney Street, Cowley, Oxfordshire. No house number shown, lazy enumerator! They have moved! When did they move?
Here is an excerpt from the transcript for 1871:-
George Jeffery 39 Whitesmith. Harriett “ 37 William “ 11 Born DecQ. 1859 in Oxford. Sorry William, no middle name! Alice G. “ 9 “ MarQ. 1862 in Headington. Alice Gertrude. Eva J. “ 6 “ DecQ. 1864 in “ Eva Jane. Emily J. “ 2 “ SepQ. 1868 in “ Emily Julia.
To find the dates of birth of the children, look on the Births, Marriages and Deaths site (freeBMD). This gives you the quarter of the year the birth of each child was registered in, (eg. DecQ. means sometime during December, or the preceding 2 months, November, or October). You also get the district where the birth was registered. The other very useful information you sometimes get, is the child's middle name. Really essential with a name like John Smith! Many apologies to the thousands (or is it millions?) of John Smiths out there, but you are much easier to find if you have a name like John Algernon Smith!
In 1871 George and Harriett have moved from 35, Albert Street, St. Ebbe, Oxford, to Sidney Street, Cowley, which is on the outskirts of Oxford, towards the south east. They must have moved sometime between 1861 and 1871. Is there any way of working out when they actually moved? In this instance we can make a very good guess! If you look at where the children's births were registered, you will see that William (the first child), was registered in Oxford, as he was born in Albert Street, St. Ebbe, Oxford. All the other children were registered in Headington, the district which contains Cowley. This most probably means they were all born after moving to Sidney Street, Cowley. Making a guess, I would say George and Harriett moved to Sidney Street sometime after the 1861 census (March/April), and before the birth of the next child, Alice Gertrude, in the MarQ. 1862. You really do have to be quite a bit of a detective in genealogy ...
So in 1871, we have George and Harriett living in Sidney Street, with son William and his three sisters, Alice G., Eva J., and Emily J.