I Haven't seen many tutorials or really much of anything involving structure blocks, so I'm going to make a tutorial involving them.
I'm not quite sure on what the practicalities would be for sharing these(maybe builds of a size limit would be useful for some people?), but hey, why not?
Obviously, to start, do /give @p structure_block or /setblock ~ ~ ~ structure_block
Right click on the block, and look at the [D] in the corner, click on it to cycle through the different modes(Save | Load | Corner and Data, which you don't need to worry about) the blocks automatically fill in the nitty gritty information, so don't worry about putting in any numbers.
A Stucture has a max size of 32x32x32. I like to put the corners at the bottom southwest and top north east corners to keep things at a standard, but any corner works. Name a corner what ever you want(in my case, "House", and name the 2nd corner the same exact thing.

The save block has to be anywhere within the 32x32x32 box, outside of it, it messes up the selection because the relative corners are more than 32 blocks away, which is the max relative position you can put in the save block. Put in the name you had for the corner blocks("House"), and click "Detect" then click "Save".

The load block is to be in the bottom northwest corner of where you want it to load(note, you have to place it one block below where you want it to be placed, because the structure loads on top of the block).
The first time you click load, don't worry, it will not load the structure, but instead will preview the area it's going to load, so you can check if it's where you want it to be. Rotation and flipping/mirroring is not easy to explain in detail, but they should be self-explanatory. To load the structure, use the name from the previous blocks("House").

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Your structure must be able to fit within a 32x32x32 area, but your corners do not need to be at the very edge, you can put the at the edge of your structure too, without having a bunch of empty space.

To find where your structure is saved, go to your saves file(Search for "%appdata%"(without the quotes) hit enter, click on ".minecraft" and click on "saves") find the world you have the structure in, and there should be a "structures" folder:
Open it, and there should be an NBT file, copy it, and paste it into the other world(you may have to create the structures folder if it is not there) Here is an example house I did: