All those suggestions rely on other people...if you want to do it solo here's how:
Buy Muon Gold...lots
Buy GOOD Stim B's (400+ healing, 35+ uses)
Get at least Novice Medic
Get good 70% kinetic or higher armor (Ubese or Composite, whichever you can afford)
Go to Tatooine, get missions for Giant Worrts and Mountain Worrts (note: you may need to group with someone to get missions that high of a level, but you don't need them to hunt with you)
Have a Macro in your Toolbar setup for /healself -- trust me, use a macro, it works quicker than typing it in or pulling the heal command out of the CTRL-A skill list.
Go to your mission, eat a Muon, attack, get your intimidate and stun on the worrt, once that's done go berzerk. Don't use unarmed hit 1 or unarmed lunge 1, you'll just burn away your HAM...heal as needed...rinse, repeat.
Tips:
Mind your Muon downer, you have 10 mins after you eat it before it hits in. Walk away from the lair and rest during the downer if needed.
Armor, though suggested above, is optional...I'm a human, I used this method without armor.
Harvest the creatures, sell hides to armorsmiths, sell meats to medics and chefs. Know the quality of what your harvesting. Get the best option. This will fund your armor and Muon Costs.
Don't use a VK like others suggest, unless it's a WELL CRAFTED VK it will hinder you more than help.
It will take about 3-4 hours of doing this solid to finish. But it's one of the quickest ways to solo it and the credit payout is decent after you sell off all those hides and meats.
Once you hit Novice TK you'll be much stronger, but this is still a decent way to level up. After you hit 1/1/1/1 in TK and get some good knucks, you can take this same approach to killing pikets on dantooine solo. But by then you'll want the armor, and you'll probably want to re-work the whole intimidate/stun/berzerk combo. There are better ways to do it but I'll let you figure those out.