When it comes to ironing, training the fabric doesn't help much. Since the subject is ironing, permanent press with creases will not be mentioned since such are seldom ironed. When ironing a shirt, iron where the seam is first, move the iron lengthwise over the seam, stretch or flatten the fabric out with one hand, then move the iron over the rest of the fabric forming a crease on the opposite side. Take care not to have wrinkles under the iron since that will make unwanted creases in the middle and water will have to be applied to remove. The garment should lay flat when ironed properly, but sometimes garments are not well made and there may be a slight twist in a sleeve requiring special attention.
There is no fast way to iron except through practice and becoming good at it. Becoming familiar with items of clothing and attention required to each item in past, helps.
If using starch, there is spray starch in a can or starch mixed in a spray bottle. Sometimes sizing works better than starch. Which one used depends on preference as to the look when finished and amount of work required.
A steam iron is generally used. If spray starch is not used, use a spray bottle of plain water and apply a light mist ahead of the iron, allowing the iron to dry the fabric.
Edit: I failed to mention heat of the iron. Do not iron synthetic clothes. Too great a risk of damage. Too easy to leave shiny spots from the iron. If synthetics are ironed use low heat. For cotton use medium heat. Always keep the iron moving. Moving the iron quickly and with experience higher heat can be used.