While Niantic still hasn't given us one-on-one battles or training, it does have events on a regular basis to keep players interested.
Events usually center around a holiday or a new season. So far, there has been a Halloween event, "Thank You" event on Thanksgiving, Christmas event, Valentine's event, Water festival, Easter event, Pokemon Day event and more.
Throughout these, there have been a common theme in bonuses and gifts. Here are some tips to make the most of future events.
During the Holiday Season event, you could earn free incubators for your first PokeStop spin each day. A pre-holiday event offered discounted incubators. So, it's safe to say that incubators will be featured in another upcoming event. The next time you are faced with a free/discounted incubator opportunity, stock up. Don't use them though. Save them for an egg hatching event where it is easier to hatch eggs or you get more candy or rare Pokemon for each hatch.
Bonus candy has been a common theme throughout the previous events. (Probably because you don't buy candy, so it doesn't hurt Niantic's bottom line.) Using your candy strategically is important during these events to get ahead in the game.
Try to save up extra candy for evolved Pokemon that you don't want to walk, but you do want to power up. Don't use it all up on evolving baby Pokemon that you've already evolved before.
Don't use your candy to evolve a Pokemon right away. If it is an event that focuses on a certain type of Pokemon -- and that's the type of Pokemon you want to evolve -- wait until the end of the event. You may just catch a pocket monster with better CP. Better CP will translate into an even more powerful evolution. I've learned this lesson the hard way, unfortunately.
Save up your Lucky Eggs and evolutions for a double XP event to level twice as fast. On the last day of the event, pop a Lucky Egg and evolve every Pokemon you can. Lucky Eggs double your XP for 30 minutes so during this time you'll get four times the XP on your evolutions. You can also time your eggs to hatch while you have a Lucky Egg activated for even more XP goodness.
Catch a Christmas Pikachu, Party Pikachu or Shiny Magikarp? Any special Pokemon you catch during an event will keep its special features when it evolves. For example, a Party Pikachu evolves into a Party Raichu and a Shiny Magikarp evolves into a Shiny Gyarados.