how to avoid blunders ?

[Site "Chess.com"] [Result "*"] 1. e4 e5 2. Nf3 d5 3. d3 f6 4. Nxe5 dxe4 5. Qh5+ Ke7 6. Qf7+ Kd6 7. Nc4+ Kc6 8. Qh5 exd3 9. Bxd3 Qe7+ 10. Ne3 Kd7 11. Bf5+ Kd8 12. Bxc8 Kxc8 13. Qf5+ Qd7 14. Qf3 c5 15. O-O Nc6 16. Rd1 Qe6 17. Nf5 g6 18. Ng3 Ne5 19. Qe4 f5 20. Qe3 Nf6 21. f4 Nfg4 22. Qe2 c4 23. fxe5 Qb6+ 24. Kf1 Bc5 25. Qxc4 Nxh2+ 26. Ke2 Re8 27. Rd5 Ng4 28. Qxc5+ Qxc5 29. Rxc5+ Kd7 30. Bf4 b6 31. Rd5+ Ke6 32. Rd6+ Kf7 33. Rd7+ Kg8 34. Kd3 Nf2+ 35. Kd4 Rad8 36. Rxd8 Rxd8+ 37. Kc4 Rc8+ 38. Kb5 Rxc2 39. Ka6 Rxb2 40. Kxa7 Ng4 41. Na3 Kg7 42. e6 Kf6 43. Nc4 Rb4 44. Rc1 Kxe6 45. Nxb6 Rxf4 46. Rc6+ Ke5 47. Nd7+ Kd5 48. Nb8 Ra4+ 49. Kb7 Ne5 50. Nd7 *

This is one of them sorry for long game

[Site "Chess.com"] [Result "*"] 1. e4 c6 2. Nc3 e6 3. Nf3 d5 4. e5 d4 5. Ne4 Ne7 6. c3 Nf5 7. a3 Qd5 8. Bd3 Be7 9. h3 h5 10. O-O c5 11. Neg5 Bxg5 12. Nxg5 Qxe5 13. Nf3 Qf6 14. Re1 O-O 15. Bxf5 exf5 16. cxd4 cxd4 17. d3 Be6 18. b3 Rc8 19. Bb2 Nc6 20. b4 a6 21. Qd2 Rc7 22. Qf4 Rac8 23. Rac1 b5 24. Nxd4 Nxd4 25. Bxd4 Qg6 26. Rxc7 Rxc7 27. Qxc7 Bd5 28. Qd8+ Kh7 29. Qxd5 *

Things that help me avoid blundering.

1) study endgames.

2) study tactics

3) play very slowly in the opening.....I play 45+45 and I often use 20-30 minutes of my time by move 15-20.

4) When you have a winning position dont get in a hurry to end the game. If there is a combination make sure it is forcing and you are calculating correctly. Do something to improve your position if the combos arent working just yet.

5. exercise regularly......blunders can happen just from being mentally tired. Physical exercise can improve you mental stamina.

6. Keep a positive mindset....negative thoughts can lead to blunders.