Microsoft Solitaire Collection

As the description says, you'll need to earn a cumulative total of 100 Event bracelets. Unfortunately, of the many different types of bracelets available, only certain ones count towards this achievement. It's a very poor design choice, so you're stuck getting many more than 100 bracelets total to unlock this achievement. 

Here are a list of the bracelets that DO count towards this achievement, and how they're earned.
 

• Perfect Event - complete every challenge in an Event. You should be doing this every day
• Point Clubs - there are bracelets for 500, 1000, 2000, 3000, etc., all the way up to 10,000 points. You are guaranteed to have the 500 point bracelet available every day, and higher ones are only available during bigger events. Getting a Perfect Event will ensure you get all Point Club bracelets that day
• Expert Dash - these are awarded for clearing an Expert Event challenge in under 5 minutes, and are quite difficult to get. You'll need to get 5 of them for "One with the Dash," so refer to it for more information
• Challenger - there are a few types of Challenger bracelets, such as ones for completing cumulative amounts of Event challenges of the same difficulty, completing challenges of the same card game in the same event, and completing cumulative totals of challenges over all Events. These will all come naturally as you earn Perfect Event bracelets

For completeness' sake, here are the bracelets that DO NOT count towards this achievement:
 

• Place Finish - these are awarded for completing an Event quickly (in real time, before others), such as first through third place, top 10, top 25, etc.
• Eventgoer - this single bracelet is awarded for participating in 10 Events

Since the bracelets for finishing Events fast don't count for this achievement, there's no need to rush each day to get them done as soon as the Events start.

As mentioned in the roadmap, for bracelets to count towards this achievement, they must be done during live Events on the day of the Event. As a result, you're stuck waiting real time for enough Events with enough available bracelets to eventually earn 100 of them. The only bracelets you are guaranteed to get every day are 500 Point Club and Perfect Event. Therefore, the maximum this achievement will take is 50 real days. However, there will continually be opportunities for Expert Dash and higher Point Club bracelets, plus you will unavoidably get some cumulative Challenger bracelets. You can therefore expect to spend somewhere in the range of 20-30 real days on this achievement, depending on how the Events fall that month.