Since plastic is all around us, in our clothes, phones, watches, and containers, you should avoid taking plastic as best as you can.
Sure, you could avoid plastic shopping bags, stop drinking bottled water, or refuse to take plastic utensils and straws, but there's more you can do.
Buy less. When given the opportunity to buy stuff, ask yourself the question: "Is this part of my necessities or my desires?". This is mainly because many products, either on Amazon or the mall, comes packaged in a form of plastic, which of course takes fossil fuels to produce.
Also, be more picky about packaging. Maybe the packaging of a certain product is one you can surely recycle, and one isn't. For example, pick the eggs that have cartons of pulp and not styrofoam or cleared plastic, and recycle it afterwards.
Buy/wash less clothes. I think we all know that clothes contain polyester fibers, which are made of plastic. Try to buy clothing made out of the least polyester, and wash them less. I'm not saying that we should sit in the same clothes for a week (yes, I've done that before), but maybe if you didn't particularly do anything (no exercise) those clothes and they're still clean, it should be fine to keep them on for another day before they need to be washed.
This isn't going to be a major component in our planning, but it would compliment all the other things others may share.