The first bunch I got from this YT video which I will link ( I did not make it so credit where credit is due but will try to recap it in short for people who prefer a written guide.

First tips come from a YT vid I found from a person named Arktix:











In short it boils down to this:


Horizon Zero Dawn Tips & Tricks

• Fire Damage Optimization: Use damage coils instead of fire coils to maximize burn damage (6x vs. 2.5x boost).
  
• Easy XP: Complete weapon tutorial quests by setting them as active in the menu.
  
• Free Gear: Trade special tokens early for free resource packs and outfits.
  
• Spear Upgrade: Do the “In Her Mother’s Footsteps” quest to boost spear damage.
  
• Best Early Skills: Prioritize Silent Strike and Critical Strike for stealth and melee efficiency.
  
• Dodging & Combat Tips: Dodge past enemies instead of away, use healing during dodges, and learn enemy attack cues.
  
• Fast Travel & Resources: Get the Golden Fast Travel Pack by hunting animals; use Focus scan to tag wildlife. Costs a fox skin and some meat...
  
• Efficient Exploration: Unlock campfires just by passing them; save often.
  
• Ammo Crafting Caution: Don’t overcraft; excess ammo is lost. Use harvest arrows to collect more resources.
  
• Best Bows & Coils: Get powerful bows early in The Frozen Wilds and farm purple coils from Scrapper piles.
  
• Side Content & Secrets: Pause the main quest before “Deep Secrets of the Earth” to explore side content.
  
• Settings Adjustments: Enable auto-pickup, motion aiming, and customize controls.
  
• Combat Optimization: Use Concentration wisely—only activate before releasing shots. Use ropecasters for easy immobilization.

Found a few more nuggets here: https://www.forbes.com/sites/insertcoin/2017/02/28/ten-things-i-wish-i-knew-when-i-started-horizon-zero-dawn/

• Health plants are mostly tall and red.(Blue and short in wintry areas)
  
• If you like you could save on using healing plants by saving at a campfire and then pick restart from save instead of healing yourself.
  
• The Tinker Perk is recommended to allow versatility in your builds and not losing the mods you replace which make this skill one of the most useful perks in the game.
  
• Some perks are less useful throughout the game: Quiet Sprint, cheaper ammo crafting, increased hacking time, increased scavenging and disarm traps.
  

Source: 10 Horizon Zero Dawn Tips for Beginners [www.keengamer.com]

Again short summarization of the tips not mentioned previously:

1) Check Out the Cauldrons

Investigate Cauldrons to gain the ability to override and control various machines, turning them into allies or mounts.

However, make sure you go into these Cauldrons reasonably well-equipped with ammunition (arrows), potions, and crafting supplies. The Cauldrons are full of robots that don’t give Aloy an especially warm welcome. You’ll also need to defeat a big robot at the end of each Cauldron to finish it. So, don’t attempt them until you’re at or above the recommended Cauldron levels ranging from 11-20.

2) Hunt Wildlife for Resources

Regularly hunt animals like boars, rabbits, and foxes to gather meat and skins, which are essential for crafting potions and upgrading equipment.

3) Craft as Much as You Can

Crafting ammunition and potions is more cost-effective than purchasing them from merchants, allowing you to conserve valuable metal shards.

4) Sell All Useless Resources for Metal Shards

Some items in your inventory are solely for selling. Check item descriptions and sell those that are marked as "useless" to free up space and earn metal shards.

5) Exploit Robots’ Weaknesses

Use Aloy's Focus to scan machines and identify their elemental weaknesses and vulnerable components. Target these weaknesses to defeat enemies more efficiently.

6) Increase Damage by Filling Robots’ Status Meters

Apply elemental attacks to fill a machine's status meter, triggering effects like burning or freezing, which deal additional damage over time.


7) Expand Your Field of View

The Horizon Zero Dawn Complete Edition PC version includes a Field of View slider that will interest some players. This slider setting enables you to expand Aloy’s field of view beyond the default setting. Doing this will enable you to see more surroundings when playing, which can sometimes be an advantage. You can expand Aloy’s view by dragging the Field of View bar’s slider to the right on the Display settings tab.