Having the right equipment for the job at hand will make for a better result.
Water blasting: Water blaster (1500 psi for general cleaning, 5000+ psi for old paint removal) (hire), overalls, gloves and full-face mask or goggles. Consider Ultra High-Pressure Water blasting at about 40,000 psi, (contractor)
Grinding- Sanding: Angle grinder (hire) and plenty of discs, (Flex O vit from ZEC), (Norton Sanding Discs), (Josco Flapper or Bluestrip) or Orbital Sander, goggles, dust masks, overalls. (ALL from Bunnings) NB: Use dustless / vacuum sanders.
Mixing: Electric hand drill and stirrer. (450 – 600 rpm) Bunnings, DTA 80mm ribbon mixer.
Application: Roller Trays, (a spare one) Handles and Extensions. 270 mm wide is suitable (wider makes corner work difficult) 5L straight sided bucket(s).
Brushes: 35- 50 mm, professional quality ($10 – 15) Paint Shop.
Roller Sleeves: (e.g. Draylon, Mohair or similar, solvent tolerant). Use 8/10/12 mm nap (15 – 25 mm for Pebblecrete). (Use short nap for smooth and longer length nap for rougher/uneven surfaces) Buy good ($15 – 25) quality. Can use lambs wool sleeves on rough/uneven surfaces. ALSO 3ins (75mm) sleeve for corners.
Masking tape: Painters Green Masking Tape – Paint shop.
Surface Temperature: Before you paint, measure the surface (not air!) temperature. It must be above 5C