Before you decide to do it, make sure you know everything up front. Most people will send you and agreement or a contract. In a lot of the cases, you would get free product for creating art for that company. Many of them do not pay you anything. You just get free product and maybe an additional discount on other things in their lines.
Consider if you really like the product and would be able to think up many uses for it. It may not be wise to be on a design team whose focus is on scrapbooking stuff when you do mixed media or textiles. Do you use that product? Can you think of multiple uses for what they want you to do? Do you have the time? Can you realistically produce the artwork that they ask you to create within their timeframe? Do you have to be active in their Yahoo group? What happens if you cannot make your monthly or weekly quota? Do you have to submit to magazines? Are you comfortable with what they are asking you to do?
It can get old fast if you are pressured and feel overwhelmed by it all. Remember, it is supposed to be fun and help you creatively. Do not do something that you don't enjoy -esp. if you are not getting paid for it. If you love it and it feels right, then go for it.
Why am I writing about this? I was having a discussion with another artist about this just today after school. She is not into the same type of art I am but she is a technique junkie in what she does. We were chatting on the phone about art jewelry. We were talking about the design teams that we have been on. I can't say that I won't do it again, but I would make very sure that it is for a product that I absolutely love and that it would be my only commitment. They would have to flood my house with product so I would get a huge creative surge. Otherwise, I would most likely pass. We were both in agreement about that. Design teams take up a lot of time. Time is a precious commodity for the both of us. We both have younger children.
Moral of this post? There is none. I am just reflecting on a phone conversation. I am not on any design team right now. INo plans of being on any. I have only a couple of swaps going right now. I am busy with school, school, and my kids. I always have a couple of art things going on to keep me motivated and creative. Kids and dh are a priority right now. A lot of sickness in my house lately. I have to take care of them. When I do find time to create, I am in my own little happy place where life goes away for awhile. Remember, art is supposed to be fun - therapy. It is no fun it you aren't feeling your groove.