With space patch collecting its a question of where do you start. The field of patch collecting is expansive. Don't let that put you off.It's a rewarding hobby. Each patch is a miniature work of art; there are so many questions as to what to collect and how to display them? Where to buy them and how much to pay?
It does pay to specialise. If you are already into space as a hobby you may already collect along a particular theme or era e.g. Mercury, Apollo, the Shuttle program or International missions. It can be further divided into official mission patches/contractor or program patches/manned or unmanned flights/commemoratives.
By far the easiest to collect are the U.S Space missions. Everyone wants a piece of a mission; it provides a connection to a flight or a particular astronaut or spacecraft. Manufacturers have been quick to fulfil demand.
The real rush for an embroidered collectable began with Apollo 11 and the first moon landings. Such was the demand at the time that manufacturers produced all of the current missions of the time and have continued to do so ever since. They also made up patches that then became the official commemoratives for the flights that did not actually have an official logo or emblem.
Today the design of the mission patch is usually a team effort between the assigned astronauts and a lot of thought goes into the symbolism.