First the obvious, play them in order. Other than that, it’s fine to go blind into the games. And because i played the games so long ago, i don’t remember thing really good. But at lesst i remember a bit.

There are a lot hidden things in these games, so it can benefit you to explore a lot, even in the overworld. The game system seems to be easy and is probably easy to play, but has a lot to find out as well. Get different skill depending on the equiped djinn oder depending on activated or not activated djinn you have different stats as well. Earth Djinn doesn’t have to go to a earth char. play a bit with them and find out interresting combinations.

Some basic pointers:

Both games are conntected and you need to play both for the whole story. Iirc they were planned as one game and later split up.

There are so-called Djinns, little creatures you collect and equip to change both skills and attributes of your party. Some are missable (Edit: Only in the third game, you can’t miss Djinns in the GBA titles, misremembered that). If you care for completion, you should look up their locations - or at least the missable ones. If you don’t, searching can be fun and the games are beatable with a fraction of them.

Instead of grinding, try experimenting with Djinn setups. Some are great for overworld puzzles, of which there are a lot, others are better for certain fights.

Speaking of puzzles, they are some of the best RPGs in that department with many overworld abilities to use. If you don’t like them, there are probably too many.

There is a third game on the DS, but as far as I’m concerned you can ignore it. It’s basically a long introduction for a new series that never happened. Only go for it if you need more after finishing both games.

Hey, so we meet again slimerancher. For anyone who’d like to know as well. I gave some hints in another comment. https://lemmy.world/comment/6610801 Cheers!