Is this common for his age?
What can I do besides giving him more practice?
You can help him strengthen this type of thinking through story telling, theater games (acting out well-known stories), manipulatives, and board games.
You can tell him the story of an exciting adventure you had together. Another day you can review it by getting him started with the story, and then ask him what came next? If it's a story he really likes, you can continue to work with it in different ways.
With either a family story or a story from a beloved picture book, you can draw some symbols or use some photographs or photocopied images from the book, mix them up, and ask him to try to put it back together, like a puzzle, and then you can tell the story based on the order he put them in -- it might end up like a fractured fairy tale, or silly, or even nonsense -- that's okay, this can be a source of fun. In other words, during this experimentation, he doesn't need to get it right.
You can make a homemade Chutes & Ladders type of game, with labeled landmarks that are meaningful in his life, or from a family adventure story, or from a picture book. An easy way of making a homemade game: take a sheet out of a big sketching pad. Sketch out the track in pencil, zigzagging gracefully and then aste the pictures in and go over it with a marker. To play, lay the paper out on a clean table. To store, put it back in the sketch pad.
Working with a big clock with movable hands, you can talk together about what he does at different times of day. Move the hands around as needed. This gives you an opportunity to use time and order adverbs.
Give him his own calendar on the wall and let him write planned activities in it, and notes about things that happened -- it's okay if he writes in silly things.
Draw a snaky number line in chalk on the driveway or in the park, and make up hopscotch-type games, such as 1 - 3 - 2 - 4 - 3 - 5, etc. If you like to do music together, you can sing or play the pattern, using the numbers as notes in a major scale.
You can do the same thing (but without the music) with the alphabet.
You can make a board game based on a track with the letters of the alphabet written on it, and index cards cut in half that get shuffled. Each card would say something like, "go back 3 spaces." You can write down the letters you land on, and see if it makes something pronounceable! I haven't tried this -- you might need to make some cards that say something like "go to the nearest vowel."
If he gets comfortable sequencing in one area, it will be a good foundation for other types of sequencing.
You are on a journey of discovery, to figure out how your son learns best and what is most fun for the two of you.