This video serves as a guide for those wanting to level up quickly in the early game so that you can recruit your companions at the experience cap that they can have when joining your party.
This is a safe route which I usually take when I want to gather a strong party early on. Tested and presented here playing with SCS on insane difficulty with double damage taken.

For reference the exp thresholds for recruiting companions are: 4K, 8k, 16k, 32k. In this guide I am aiming to reach the 32k cap as soon as possible, at which point you can assemble your entire party, all coming in at level 6 :)

This guide can be completed with any class and any kit (with the exception of one specific enemy which requires consistent ranged damage - although this enemy is optional for this guide).

Quick guide steps:
00:00 Assembling money and gear (0xp)
15:51 Mutamin's Garden (25000xp)
29:40 Marl (900xp)
30:46 Firebead's book (300xp + Scroll case)
32:30 Landrin's House (deliver later)
36:45 Joia's Ring (400xp + Ring of Wizardry)
39:45 Tarnesh (I derp)
43:02 Deliver Landrin quest (800xp)
45:02 Perdue's sword (deliver later)
47:06 Shoal the Nereid (optional 5000xp)
50:42 Melicamp (2000xp)
56:16 Tenya (2000xp)
1:04:00 Deliver Perdue's sword (500 xp)
1:06:12 Gathering example companion
1:09:12 Alternate way to deal with Basilisks (No Xzar recruitment)

*Note*: The paws of the cheetah were consoled in to make walking sections go faster, they are not used in any way to avoid combat or kite enemies. This is not an item you can acquire at this point in the game.

More 2nd edition advanced D&D adventures:
BG1 playthrough:    • [BGEE #00] Baldur's Gate Playthrough ...  
SoD playthrough:    • [BGSoD #1] Siege of Dragonspear Playt...  
BG2 playthrough:    • [BG2EE#01] Baldur's Gate 2 Let's Play...  
IWD playthrough:    • [IWD#01] Icewind Dale Let's Play - Pa...  

Thank you very much for watching :D Hope it helps!