If you have spare Leve Allowances and want to level crafts the fastest, rather than calculating out what you'd need to grind to get the exp needed, I'd recommend instead mathing out how many times you need to do X leve to get yourself to the next level that is a multiple of 5.

For instance, if you have WVR at level 30 and want to get it to 35, you know that you'll need a total of 949,400 experience. The following Leves are available to you:
Courier (Ul'Dah to Costa Del Sol): HQ Linen Chausses (95,640 exp)
Single (Ul'Dah): HQ Velveteen Robe (60,560 exp)
Single (Costa Del Sol): HQ Velveteen Gaskins (60,560 exp)

If you're willing to do Courier leves, you'll need to make 10 HQ Linen Chausses and then spend 10 Leves to teleport between Costa Del Sol and Ul'Dah to get from WVR 30 to WVR 35. If you are lazy and have tons of leves to spare, you can instead make 15-16 HQ Velveteen Gaskins or Velveteen Robes and then spend 15-16 Leves running back and forth from the Levemate to the buyer.

And so on. You can basically get any craft from 30 to 50 by spending ~43 leve allowances on courier leves. You can start before level 30, obviously, but that's where this method really starts to shine.