The kusama crowdloan season is here, and here is a simple guide on how to join the parachain auction using polkadot.js . For 2 days until 11-June they are having a special 10% for early bird bonus and another 5% extra if you use my link below.
- Lease Period: 48 Weeks.
- Reward: 12 KAR for every 1 KSM contributed.
- Vesting: 30% liquid upfront, 70% vest over lease period.
- Referral Bonus: Referral code recipients will receive 10% additional KAR to split between referrer and referee.
- Eligibility: no KYC is required, but participants must agree to Terms & Conditions where participants from certain jurisdictions are excluded
1.set up your polkadot.js wallet, make sure it is set to the kusama blockchain and already has ksm inside the wallet address. Kusama relay chain address begins with capital letters.

2. sign up via a referral link, both will get 5% bonus
3. at the crowdloan page, tick the 3 checkbox

4. click on "connect polkadot.js" and type in amount of ksm that you wish to invest
5. type in your email. In this example, i choose 3 KSM and will get 36 KAR + 3.6 KAR (10% early bird bonus) + 1.8 KAR (5% referral bonus)

6. click on "submit contribution" , it will then ask you to confirm in the polkadot.js. Confirm it in polkadot.js and it is done

7. waiting after confirmation

8. Result of submission

Will I get my KSM tokens back if Karura doesn’t win the auction?
If Karura does not win the initial auction, it will continue to bid in the subsequent auctions. If Karura fails to win any auction for six weeks after the beginning of the crowdloan, then it will end the crowdloan and return all funds to holders.
Other FAQ here https://wiki.acala.network/karura/crowdloan/faq
Do join via my referrral and we both get 5% extra