Spellcaster - what's your routine?

I've usually had terrible luck with my spellcasters learning magic through practice or experimenting (believe it or not, the interaction can "fail" so your sim ends up learning nothing even when there's stuff to learn.), so I'm more likely to either have them go to the magic realm to learn from the sages or... just dig the tomes out of debug and have them read them at home.  It's not a cheap solution, but it is one that doesn't require me to maintain a friendship with the sages and allows for a more curated spell list. (not to mention the lack of loading screens)

Like Atreya33, I'll have active spellcasters, who specifically work on their magic and learn most/all the spells, and I'll have passive ones who pick up Scruberoo and Repario... and once they eventually level up enough, Delicioso, and that's about it.

I've also started fencing off the cauldron so that the sims won't autonomously make mac and cheese.

What rank is your spellcaster? If they're at the top I'm not sure the experimenting adds anything. 

The ranks are Apprentice, Neophyte, Acolyte, Adept, Master, Virtuoso

My sim, Julianna, is Virtuoso rank but it's been 5 years and  I've completely forgotten most of the gameplay.

When I'm playing a new spellcaster, my routine is: 

1. Visit the Realm of Magic 
2. Ask each Sage to teach me a spell 
3. Ask each Sage to teach me a potion (I usually make both requests at the same time) 
4. Search for Tomes until I find something 
5. Practice each type of magic until I've learned all the spells available for my current level 
6. Experiment on a cauldron until I've learned all the potions available at my current level
7. Practice Practical Magic until I level up (the Practical spells are the ones I consider most useful) 
8. Go back to step 2 
9. Go home when my Sim gets tired, overcharged, or has something else to do 

I don't usually bother with making any potions except the Potion of Plentiful Needs, which only requires an apple. Instead, I use the CopyPasto spell to duplicate the potions I was given as I learned them. I'm careful to always keep at least one copy of each potion, so that I won't have to make them.

You can learn all the spells once you reach Master level, and I think that applies to potions too, so after that it's just a matter of continuing to use your magic so you can get all the perks.

I have two different routines for spellcasters

Active spellcasters: these spellcasters are actively working on spells and levelling up 

1. Learning spells by buying and reading tomes or experimenting 
2. Brew potions or experiment on the cauldron .
3. Visit the magic realm on a regular basis 
4. Earn a living in a way that suits spellcasters. (I may add storytelling circumstances to suit the setting) This can be a gardener who is grow (magical) potion ingredients, a teacher (working at a magical school) or a writer (writing spellbooks). Obviously a paranormal investigator works too. 
5. Have hobbies, activities that seem fitting. The new jewelry station feels perfect for this. Other options are collecting, herbalism, archeology, writing, flower arranging,... 
6. No quick 'cheats' I have rules against earning money by copypasto. I use a mod to make the potion of plentiful needs to be less powerful. 

Passive spellcasters : they live regular lives and being a spellcasters is part of their identity rather than an active goal. They only level up very slowly. 

1. Live regular lives and do whatever they want. 
2. Occasionally use some spells, mainly practical spells in every life.

Over the course of their lives my spellcasters can switch from active to passive and the other way around. 

My Spellcasters are: 

Mystics with Medium Crystal Ball that befriends Guidry & Bonehilda; that also makes magical Crystal Jewellery & has the Paranormal Career.💎🕵️‍♀️

Seasonal Fairies with their Seasonal Gardens, maybe a magical Unicorn & has the Garden Career.🧚‍♂️🦄

Alien/Spellcaster Hybrids in the far future that rides the Spaceship, X-Wing, visits Sixam & has the Engineer Career.👽🤖 

Fallen Angel Couple.  The hubby is a Spellcaster/Vampire Ex-Demon.  The wifey is a Spellcaster Ex-Angel.  They secretly fell-in-love & got casted onto Earth.  They now have triple EarthAngels.😇😈

Jeannie Genie living in her Magic Bottle doing home hobbies cause she's stuck in her bottle.🧞‍♀️⚱️

What can I say, I have a lot of imagination & I only play vanilla.🤗

It's been awhile for me too, but crystals can be used in potions so are very helpful to have around. It's also good to have a little garden to grow the plants needed for potions as well.

Experimenting at the cauldron can help your Sim learn new potions, but it's not guaranteed. It will help raise their level. You can also practice magic. It's good to go over to the Magic Realm to learn new potions and spells from the sages. I think you can also duel for knowledge.

Some other packs I think go well with Spellcasters are Outdoor Retreat for herbology. There is a mod that allows you to make herbology potions in the cauldron too. Also the new crystals pack has a witchy feel.

Also if you use mods, Ilkavelle has some custom careers for Spellcasters.

I admit I don't play with the spelcasters much. I used the cauldron to make industrial  quantities of cheese macaroni and put the spell books up for sale in a book shop and that's about it. The Harry Potter type spells and magic never appealed to me and there is not much to do in the magic world if you're not a spellcaster either. I should probably try play them sometime. The magic broom rides look cool. 

Hi Simmerville, has your spellcaster already learned all the potions available for his current rank? If so, you won't learn any more potions from experimenting, you have to have him rank up to the next level.

Are you getting magic xp from experimenting at least? (the xp bar in the bottom of the spellcaster needs panel)

The crystals are probably for potion ingredients. Look in the spellbook and you'll see each learned potion has a recipe with the ingredients showing :)