This is a technique I have developed when I have low energy or need to do a quick reading. I often find typing up long readings is what drains my energy, more than the readings themselves.
First use a question that begins ‘How can I improve…? Questions beginning with How can be very powerful. See this post by mep who explains this in more detail.
[*] Draw three cards as you would do normally.
[*] Only write up to two sentences max for each card.
[*] I would recommend not looking in books. Gut instinct is usually right. Limiting to a couple of sentences means you are more receptive to the messages of the cards, and less likely to overanalyse.
[*] You can do this with or without a spread. I usually do mine without.
This exercise is good if you are out of practice! I have an example here. Be warned that this contains speculation for Torchwood: Children of Earth, (Torchwood series 3) which airs on BBC America on July 20th.