Perfect Prep: The Secret to a Flawless Finish

We all love the fun parts of decorating — choosing the perfect paint colour, rolling on that first coat, and seeing a room totally transform. But if I'm being honest, there’s a not-so-glamorous stage that most people try to rush (or skip completely), and that’s prep.

I know it’s tempting to dive straight in with your paintbrush, but if you want smooth walls, crisp lines, and a finish that actually lasts, proper prep is where the magic happens. Whether you’re freshening up a spare bedroom or doing a full home makeover, spending a bit of time on the groundwork will make your topcoat look 10 times better — and you’ll thank yourself later.

So, let’s walk through each step of surface prep and the products I genuinely rate to help you get it done right.

What Prep is needed?

If you want to read up on a specific prepping step use the index to skip ahead!

Step 1: Start with a Clean Surface

First things first — you need to clean your surface. Any dust, grease or old product lingering on your walls can stop paint from bonding properly and lead to issues down the line like peeling or patchy coverage.

A quick dust is always a good idea, especially in corners and around skirting boards, but if you’re dealing with anything a bit grubby (kitchens, hallways, light switches — I see you), then reach for a degreaser. Zinsser Universal Degreaser & Cleaner is a brilliant go-to for general grime.

Got mould or mildew? That’s where Zinsser Mould Killer & Remover comes in. It’s ideal for bathrooms, kitchens and anywhere that tends to get damp. It clears away stains caused by mould and fungus and gives your fresh paint a much better chance of lasting.

If you’re prepping an especially tricky area, I’d also recommend the Krud Kutter range. These are real problem solvers:

For more detailed information on each spray in the Krud Kutter range, have a look at the spotlight blog I wrote here.

Step 2: Scrape, Sand & Smooth

Once it’s clean, it’s time to take a good look. Are there flaky paint patches, peeling wallpaper remnants, or uneven areas? This step is all about smoothing things out so your finish looks — and feels — flawless.

If there’s any flaking or peeling, you’ll want to start with a scraper. The Axus RUT (Really Useful Tool) absolutely lives up to its name — it’s a scraper, crack rake, roller cleaner, nail remover and more, all in one. For larger areas or high walls, the Prep Long Handle Wall Scraper gives you that extra reach (and saves your arms too!).

When it comes to sanding, don’t be tempted to skip it — even lightly scuffing a surface will help paint grip better. For walls and large flat areas, the Ciret Prep Hand Sander or a roll of Mirka Aluminium Oxide Sanding Paper will do the trick.

For trickier corners or textured surfaces, I love the Axus Arystox Flexible Sanding Pads — they’re bendy, clog-resistant, and last ages. And for more delicate jobs, like gently knocking back between coats or smoothing woodwork, Rodo’s De-Nib Pads are fab.

If you prep well here, your paint finish will thank you — it’ll go on smoother, last longer, and look ten times better.

Step 3: Fill Any Imperfections

Next up — filling. Cracks, dents, even pinholes can really show through once you’ve painted, so this is where you even everything out and get your walls looking good as new.

But not all fillers do the same job, so it’s worth picking the right one:

And for anything bigger — think a knocked-in bit of plaster or a hole from DIY gone wrong — try Gyproc EasiPatch Plasterboard Patches or Toupret Adhesive Joint Scrim Mesh Tape to reinforce the area before filling. It’ll give your filler something solid to grip onto and help prevent it from sinking or cracking later on.

Step 4: Mask It Right

Almost there! Before the paint comes out, you’ll want to protect the bits you don’t want painted. Trust me, masking properly takes 10 minutes and saves you an hour of touch-ups.

If you’re working on freshly painted walls (within the last 7 days), Masq Sensitive Tape is your safest bet. It’s designed to be gentle, so it won’t lift off that lovely fresh paint when you remove it. Masq also has a full range of tapes for different jobs — their Low Tack Painters Tape, Ultimate Painters Tape, and Superior Painters Tape all have slightly different tack levels, so there’s something for every surface and scenario. Have a look at our Masq Tape collection to read up on each tape.

For large areas, trims, or awkward edges, I swear by Masq Covermasq Tape & Drape. It’s a clever 2-in-1 that combines masking tape with a lightweight drop film — perfect for protecting surfaces quickly and easily.

And don’t forget the floors! If you want something reusable, go for a Cotton Twill Dust Sheet — heavy-duty, hardwearing and ideal for most rooms. If you’re after a quick and easy disposable option, the Axus Red Series Plastic Sheets do the job nicely. For carpeted areas, try ProDec Carpet Protector, and for hard floors, ProDec Hard Floor Protector — both are self-adhesive and stay in place while you work.

Step 5: Prime or Seal (Don’t Skip This!)

I know it’s tempting to skip primer, especially when you're eager to get that first coat on — but honestly, this is one of those steps that makes all the difference. A good primer or sealer creates a sound surface for your paint to grip to, stops it soaking in unevenly, and helps block out any problem patches underneath.

If your surface is chalky, damaged, or has been previously wallpapered, Zinsser Gardz is a brilliant choice. It’s a sealer that soaks in and stabilises the surface, making it ideal for flaky plaster or anything that feels a bit dusty or fragile.

For glossy or tricky surfaces like MDF, varnished wood, or even water stains, Zinsser B-I-N is the one to reach for. It’s a shellac-based primer that blocks stains, knots and stops bleed-through — and it dries super fast too.

Painting fresh plaster? You’ll want to mist coat first — that just means diluting your paint with water to help it soak into the surface. I usually use Leyland Hardwearing Matt, thinned by about 10%. If you’re not sure how to do this, I’ve written a whole blog explaining what a mist coat is and how to do it right.

And if you’re unsure which primer is best for your project, you can always check out my full Zinsser Primer Guide — it’s packed with everything you need to know, no matter what you’re painting over.

Bonus: Prepping Woodwork?

If you’re painting doors, skirting or architraves, you’ll want to follow the same cleaning and sanding process — but with a few extra steps.

After sanding, use Leyland Fast Drying Undercoat as a base, and finish with something like Johnstone’s Acrylic Durable Eggshell for a scuff-resistant finish that can even be colour matched to your walls if you're into the seamless colour-drenched look.

Ready to Prep?

Prepping might not be the most exciting part of a decorating project, but it’s hands down the most powerful. A little bit of extra effort here sets the stage for that smooth, professional-looking finish we’re all after — and it’ll save you from having to redo it in six months' time.

If you’re not sure which prep products are right for your space or surface, just pop us a message via  WhatsApp or on email— we’re always happy to help. Whether it’s flaky walls, damp corners, or a shiny surface that won’t play ball, we’ve got a product (and a plan) to get you sorted.

And don’t forget to tag us in your before & after pics on Facebook, Instagram or TikTok — we love seeing what you’re working on! And we love sharing our community's wins on our socials, in our Blogs and on our Newsletters!

Happy prepping,
Helen x

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