I used to be able to clean my drain by picking out the hair and fat from it but it has become worse and worse. Can I use hot water + draino (the chemical) + plunger to clean it up?
I use "Zep Crystal Heat" drain opener that I buy from Home Depot or Lowes. It contains sodium hydroxide so wear protective gloves, eye wear and do not breathe the vapors. Read the label and follow their directions. I usually double or triple the amount they say to use. First, remove the drain cover, then run the hot water to get the standing drain water hot which makes the product more aggressive, open a window in the room, pour in the stuff, turn on the vent fan and get out of the room. To check on the progress, I hold my breathe, walk into the area, check and get back out. When the vapors stop, I re-enter the room, turn on the water to flush the drain and "shazam" the drain is clean. This works for me.
I have achieved really good results with a flexible plastic drain cleaner such as the Cobra or Zip-It type illustrated here. No chemicals required and it removes incredible amounts of hair and gunk from deep in the trap.