Sorry for the delay in replying.
Have you tried Memory League yet? You don’t need to wait 1-2 years before participating in memory sports. 
Try the images game first. Simon’s peg list system works well. It’s described here:
To find tips for each event, you can search the forum with queries like this:
https://forum.artofmemory.com/search?q=%23memory-league%20images
Include the #memory-league hashtag in the search box to limit the search to the Memory League topics.