Cleaning a chimney safely involves a few clear steps and precautions. Here’s a practical, high-level guide you can follow, along with safety notes and when to call a professional. Direct answer

• Prepare and protect: Clear the area around the fireplace, lay down a drop cloth or plastic sheeting, and wear protective gear such as goggles, a dust mask, and gloves. This reduces soot spread and protects you from debris.
• Inspect from below and above: Check the fireplace opening, flue, and the chimney crown/top. Look for signs of creosote buildup, loose bricks, cracks, or animals' nests. If you see significant damage, get a professional inspection rather than attempting DIY cleaning.
• Choose the right tool: Use a chimney brush that matches the flue diameter. For masonry chimneys with clay flue liners, a sturdy wire brush is common; for metal liners, a nylon or polypropylene brush is typical. Ensure you have long rods to reach the full height of the chimney.
• Remove debris at the bottom: Place a drop cloth or tarps inside the fireplace to catch soot. Have a shop vacuum with a HEPA filter ready to clean up afterward.
• Brush from the top or bottom: The traditional method is to sweep from the top downward, guiding the brush through the flue with steady, controlled motions. If cleaning from the bottom, insert the brush from the firebox and work upward, then feed more rod length as needed. Clean the entire length of the liner or flue, including any tees or joints.
• Clean and remove creosote: After brushing, collect loosened creosote and soot from the fireplace using a shovel or a vacuum designed for ash. Do not leave loose creosote in the fireplace.
• Final check and test: Reinstall the cap or rain cover if you removed it. Inspect the flue again for any remaining buildup. A smoke test (light a small amount of smoke and observe its ascent) can help confirm your chimney is drafting properly. If smoke spills into the room, stop and consult a professional.
• Schedule regular maintenance: For wood-burning fireplaces, plan a professional chimney sweep at least once a year, ideally after the heating season ends. If the fireplace is used heavily or has a metal liner, more frequent cleanings may be needed.

Safety notes

• Creosote is highly flammable; if you see thick, tar-like deposits or experience frequent downdrafts, call a professional.
• Do not use metal brushes on vinyl or non-metal flue liners, and avoid aggressive scrubbing that could damage the liner.
• If you notice cracks, missing mortar, or damaged crown, stop DIY cleaning and hire a certified chimney sweep to assess structural integrity and proper repair.
• Work with proper ventilation and avoid generating dust in living spaces; seal off the area as much as possible to minimize soot spread.

What to consider when deciding DIY vs. professional

• DIY is reasonable for light cleaning of a clean, intact chimney with a masonry clay flue and no signs of damage.
• Professional service is recommended if there is heavy creosote buildup (a few millimeters or more), visible damage to the flue or crown, animal infestations, or if the chimney serves a gas appliance or older wood-burning system with a complicated liner.

If you’d like, share details about your chimney (flue type, fireplace type, how often you use it, and whether you’ve noticed smoke backing up or unusual odors). With that, a more tailored, step-by-step plan can be provided.