Take advantage of off-leash opportunities and spend a few minutes training your dog. The higher number of distractions can create a much higher return on that time investment.
Back yard practice sessions
If you've got an enclosed back yard, you can take your recall practice out of the house and into a controlled real world scenario. Birds chirping, wind blowing, the sniffs, and the neighborhood noises all vie for your dog's attention.
Come is one of those cues that I want my dog to execute with precision every time I call.
If you're playing with your dog outside, you can also integrate practice with drop it, take it, and leave it. Starting this practice in your own backyard makes it a little easier for your dog to focus on what you're asking. It also sets a precedent that even when you're playing outside, you expect your dog to follow your cues.
Another advantage to training in your own back yard is that other people you trust can help. If you have children, they can work with the family dog outside. If you have pet sitters or dog walkers or neighbors who like to visit, they could potentially ask your dog to drop something or to leave something alone.
If you don't have a backyard, you could try arranging a playdate with another dog who has a backyard. While a completely new environment and the other dog will be distractions for your dog, you could try training. If your dog is not being successful, walk your expectations back a step or two and ask your dog to do something you know they can be successful at.
Empty dog parks
I'm no longer a fan of dog parks. After having Bernie for two years now, I've had entirely too many negative experiences at dog parks that make me question the goodness in humanity.
We are fortunate; however, that at one of our frequent walking destinations there are three dog parks to segregate small, medium, and large dogs. If we walk by the dog park at a non-peak hour, oftentimes one of those three areas is empty. I take advantage of that empty lot and let the pups run around for a bit. Then we train for a few minutes.
Depending on how you feel about dog parks and whether you think your dog is ready to be tested in that highly enjoyable play place for them, you could try practicing skills at the dog park. At the very least, the dog park is a great litmus test for your dog's recall ability.
If a new dog starts to enter the gated area, you call your dog. If your dog responds by coming to you, then your practice with recall is paying off. But if your dog rushes the gate and ignores you, you know you've got work to do.
If you're taking your dog to daycare, be sure to update the staff there about the cues your dog has learned. Let them know which skills you're really trying to hone and how you're working with and rewarding your dog. They may not have time to work one-on-one with your dog every time your dog is there, but even a little practice with basic cues pays off over time.
Simulate an off-leash experience
Buy a 30-foot to 50-foot training lead. Find an open field or empty parking lot where you can practice skills outdoors, but with a different kind of safety net. It's not the same as allowing your dog off-leash, but if you don't have a safe off-leash option, then using a training lead works in a pinch.
When we lived in our condominium, the complex had a tennis court. During cooler weather, I'd take Bernie on our walk, but we'd stop at the tennis court on our way home. I'd swap his leash for the longer training lead and we'd spend 20-30 minutes practicing various skills. Every few minutes, I'd throw a favorite ball a few times as well to keep him interested. With a walk, a few sessions of fetch, and a few training rounds, Bernie would arrive home pooped!