I am personally a firm believer that a good serama should pose naturally with either no prompting or a little gentle persuasion. I am against the use of cruel training methods to force a bird into pose. It very much saddens me to see videos of birds being chased about their pens with a stick prodding and poking them whilst they are clearly distressed by it and reluctant to stand because of fear or no natural incline to do so.
Here is one of my young males being trained for the 1st time. I use only gentle stroking by hand to enourage not force him to stand.
Of course I always introduce my birds to the judging stick, they all know not to fear it. To get the birds used to the stick I gently stroke their breast with it so they learn to enjoy it and realise it will not harm them. The reasons I introduce the birds to the judging stick are not for training the birds, but to make them aquainted with the idea that if they happen to go to a show and the judge (or anyone else for that matter) should poke them with a stick that there is nothing to worry about.
Some birds do require some attention with regards to encouraging and giving confidence so that they may pose. I believe that allowing the bird to approach you then gently using a finger, just stroke under the chin and on the chest. Most birds enjoy this, provided it is practised regularly. Do not expect instant miracles.
I start handling my chicks from birth, this way they never fear you, Im usually present at all their hatchings so I am basically mother hen so they trust me. I hatch in small batches so that I never have too many chicks so all get handled and I don't miss any.
Here are some pictures of one of my 2010 bred young males being encouraged into a pose with gentle stroking of his chest and chin.
An excellent image to show size comparison of one of my A size serama males with my own hand. A very small bird.