Just roasted another batch today. I usually do about 1 lb at a time to last me almost 2 weeks. Takes 20 minutes/batch but you only have to be there for the final 5. Main thing is good ventilation. This is not an in-the-house thing if you like darker roasts. I roast in the garage with the door and windows open.
https://www.sweetmarias.com/instructions
I starteted with various DIY roasters (ther whirlypop/air roaster was the best), roasting on the porch. Finally graduated to a Behmor drum roaster.
It's an investment that pays off after a couple years. Green beans cost about $6/lb (roasted weight) versus about $12/lb for premium coffee, delivered. If you go through 2 lbs/month, that's a $144/yr savings. You get better control of your roast darkness, plus have endless options on varietals and blends, and of course the freshest coffee possible.