Great — for a hot, humid tropical climate like Sri Lanka’s you want lightweight, non-greasy, sweat/water-resistant products that control shine, protect from strong UV, and keep the skin barrier healthy. Below is a compact routine (morning + evening + extras) plus specific product suggestions in three price tiers and quick buying notes.

Why these choices (short):

• Humidity → skin tends to be oilier and more prone to sweat/heat rash, so prefer gel/lotions, water-based serums and matte or gel sunscreens. (exploratoryglory.com)
• Daily, broad‑spectrum SPF (SPF 30–50+) is essential and reapplication is important in tropical sun. Choose lightweight, non‑comedogenic, sweat/water‑resistant formulas. (verywellhealth.com)

Core routine (simple)

• Morning:
  1. Gentle gel cleanser (remove sweat/oil).
  2. Lightweight water‑based serum: niacinamide for oil control/pores or hyaluronic acid for hydration.
  3. Oil‑free, gel or lotion moisturizer (if you’re oily you can skip heavy creams).
  4. Broad‑spectrum sunscreen SPF 30–50+, preferably a matte/gel formula and sweat/water resistant. Reapply every 2–3 hours if you’re outdoors or sweating.
• Evening:
  1. Cleanser (double cleanse with oil cleanser only if you wear heavy sunscreen/filters).
  2. Targeted treatment (retinol 2–3×/week if anti‑ageing, or a BHA for recurring breakouts).
  3. Lightweight moisturizer or gel.
• Weekly: gentle exfoliation (AHA/BHA) 1×–2× to prevent pore congestion in humid weather.
• Extras: blotting papers, facial mist, aloe vera or after‑sun gel for sunburn.

Key product features to look for

• Cleansers: sulfate‑free, amino‑acid or low‑pH gel cleansers.
• Serums: water-based niacinamide (controls oil/pores) or hyaluronic acid (light hydration).
• Moisturizers: “oil‑free”, “gel”, or “lotion” and non‑comedogenic.
• Sunscreen: broad‑spectrum, SPF 30–50+, “matte / dry‑touch”, gel or watery texture, water/sweat‑resistant, non‑comedogenic. Tinted mineral sunscreens can reduce white cast for darker skin tones. (verywellhealth.com)

Specific product suggestions (examples that suit humid/tropical climates) Note: availability varies; I list budget, mid, premium options and examples commonly available in South Asia or online.

Cleansers

• Budget: COSRX Low pH Good Morning Cleanser (gentle, low pH, suitable for oily/combination).
• Mid: La Roche‑Posay Effaclar Gel Cleanser (for oily/acne‑prone).
• Premium: Kiehl’s Facial Fuel Energizing Face Wash (light, energizing).

Serums / Treatments

• Niacinamide (oil control, pore refining): The Ordinary Niacinamide 10% + Zinc 1% (budget); Minimalist / The Derma Co niacinamide serums (mid).
• Hyaluronic acid (light hydration): The Ordinary Hyaluronic Acid 2% + B5; Dr. Sheth’s / The Derma Co hyaluronic gel sunscreens combine hydration + SPF for humid climates. (healthshots.com)

Moisturizers (gel / oil‑free)

• Budget: Neutrogena Hydro Boost Water Gel (light, water‑based).
• Mid: Clinique For Men Oil Control Moisturizer / COSRX Oil‑Free Ultra‑Moisturizing Lotion (light textures).
• Premium: La Roche‑Posay Effaclar Mat (mattifying moisturizer).

Sunscreens (most important product)

• Budget / easily available: Biore UV Aqua Rich Watery Essence (watery gel texture — great for humid climates), Neutrogena Ultra Sheer Dry‑Touch SPF 50+. (theguardian.com)
• Mid: Dr. Sheth’s (Centella or Ceramide variants) and The Derma Co gel sunscreens — many reviewers/roundups call these fast‑absorbing, matte options for humid/monsoon seasons. (etadviser.com)
• Premium / dermatologist picks: La Roche‑Posay Anthelios (facial formulas), EltaMD UV (if you can source it) — both recommended by dermatologists and reviewers for consistent protection and skin‑friendly formulas. (verywellhealth.com)

Acne / oil control extras

• BHA (salicylic acid) leave‑on treatments 1×–3× per week to keep pores clear.
• Oil control papers and mattifying primers help during the day.

After‑sun / soothing

• Aloe vera gel or lightweight gel containing panthenol to soothe sunburn or heat‑rash prone skin.

Practical tips for Sri Lanka / tropical use

• Use a lightweight sunscreen every day — even if cloudy — and reapply when outdoors, sweating or after towel‑drying. (theguardian.com)
• If you’re outside a lot, consider a sweat‑resistant SPF and carry a small travel‑size sunscreen or a sunscreen stick for quick reapplication.
• Avoid heavy creams in daytime; store products in a cool, shaded place to preserve stability in heat/humidity.
• Patch test new products (higher humidity can make reactions show faster).

If you want, I can:

• Build a specific 4‑product routine within your budget and link to locally available options in Sri Lanka (online shops / pharmacies), or
• Suggest exact product SKUs that are currently highly rated and widely available in South Asia.

Which would you prefer?