There ain't any shortcut in slayer I'm afraid.
Here are some of my personal two cents:
1)
Just treat it as training combat. Time flies really fast.
2)
If you've done smoking kills, use Sumona to get task if you want fast xp.
Don't use fairy master. She gives a lot of 1 - boring 2- poor xp 3 - bad money tasks.
Don't use shilo master either. Even though his task are really nice xp,
since sometimes he gives ridiculously annoying tasks like black demons, skeletal wyverns and such,
it's a waste of time and points if you keep getting those and cancel.
It's also decent money if you trade the points for runes (35 pts for 1k mind and 250 death)
3)
If you get tasks like dagannoth or kalphites, cannon them. Your task will be done in less than 30 mins.