A good carrier is a lifesaver, but a bjorn is hard on both baby and mom due to the design. Look into an ergo, boba, or beco. I love the beco butterfly 2. It has an internal harness that enables you to do a back carry without help or trade baby from one parent to the other easily. Just practice at home over a soft surface.
I like those little plastic linking rings. Hook one through toys or sippies and then onto stroller so toys cannot fall to the ground. They can also be used as a clip to tether a lightweight blanket to the stroller so it doesn't blow.
A good hat with a wide brim all they way around would be good. I would also be sure the baby's legs, at least past the knee, and feet are covered because they can sunburn while sitting in a stroller or carrier.