-Apex : an individual triangle of cards shaped like this - /\
-Storey: a "floor" of cards, a five storey card house has 5 rows of cards on top of eachother
-Card: what you use to build the house. I take that you know this already. I reccomend NON GLOSSY regular playing cards.
Step 1: Construction up to a two storey tower and tips for building
OK STEP ONE!
this is quite simple, firstly you have to make what is called an Apex. To do this, place two cards against eachother with the playing faces pointing inwards in a triangle shape like in the picture. It would be ideal to make a line of these before going any further, without them falling over. you can line them up like dominoes and push them over when ready to proceed. this is a frustrating step, so it's good to get practise.
when you think you're ready to go further, build two apexs next to eachother, so you can "roof" them.
This is a lot simpler than it seems.
Take a card to be the "roof" piece, and place it (in the air, above the two apexes [apexs, apexi?] ha) hold it and lower it til it is about a milimetre or two above them, then let go. DO NOT PLACE it on, as this is far more likely to collapse it.
-Once the "roof" piece is on, it may have adjusted the apexes which support it. It is now safe to adjust these with gentle movements, as you will find roofing it makes it much more versatile. It is VITAL when you make larger towers that after every collapse on an upper storey, or placing of a roof, that you adjust the apexs below accordingly.
FINALLY! to make a two storey tower, the one you see in the picture, take your roofed apexs and make a third apex. As this is the only apex on this storey, you can hold it with both hands as you put it in place. As with roofing it is essential that you do NOT place it on, as this will put pressure on the rest of your tower, but drop it from about a milimetre above, guiding it with your hands, then very gently making a balance on it. If it collapses, adjust the apexs on the bottom storey , as they will have most likely moved.
Placing will have less effect here as it is only the first apex on the second storey, but i suggest you do the 'drop' method to get the hang of it, as it is essential later.
I recommend making a few of these two storey towers to get the knack of placing an apex on an upper storey.