Sow seed somewhere warm (18-21C - airing cupboard, or propagator, or in a pot covered with clear plastic bag on a warm windowsill) - I start mine off first week of March but check the instructions on the seed packet
Prick out to individual 3" pots, and grow on at 13C-18C and ensure that the minimum temperature does not fall below 10C (at which point they will "stall" and take ages to get going again)
As the rootball fills the pot then pot-on to a pot that is 1" - 2" larger in diameter.
I keep mine in an unheated conservatory (which is much warmer than my unheated greenhouse, and as it is attached to the house so if it is likely that the temperature will fall below 10C I can bring easily them in for the night ... the conservatory has good light like a greenhouse, and much better than a windowsill).
Around mid-May I plant them out in the unheated greenhouse. They can be in grow bags, pots, or the greenhouse border (which is what I do).
Train up a cane (I have mine right next to the glass) to to about 5' and then pinch out the main tip to encourage side shoots. I train the laterals to horizontal wires I have permanently attached to the sides of the greenhouse. Pinch out each lateral after the fifth leaf.
You then need to hand pollinate the flowers. I just break off a male flower and insert it into the female flower. (The female has a baby fruit behind the flower, the male flower just has a very skinny stalk).
Feed with the same fertiliser as you use for your Tomatoes (e.g. a proprietary Tomato fertiliser)
I recommend the Sweatheart variety for a beginner. They tend to produce fruits even if you don't have time to do the training, and the fruits are a decent size so if you only get a few they will still feed a several people ... whereas most of the more poncy Charantais and Cataloupe types that I have grown very rarely produce 4 fruits per plant and they produce smaller fruits.