Go to http://primes.utm.edu/primes/home.php.

Step 1: For people who have not submitted top-5000 primes previously, create a prover account:
1. Select 'Submit' on the lower left side under 'Join in'.
2. Select the 'click here to create a prover-account' link in the middle of the page.
3. Fill out the form and submit it. You will be assigned a prover account.

Step 2: Create a proof code:
1. Go to the home page in the link above and select 'Index' on the left side under 'Provers'.
2. Next to 'search prover-accounts', type yours and press enter.
3. Click on your prover account (there may be one or several) and press enter.
4. Towards the bottom, click on 'Create a New Proof-Code' and press enter.
5. If necessary in the little pop-up box, type in your user name (prover account) and password and press enter.
6. You should now have a list of proof programs. Select LLR.
7. In the space below all the programs, type in 'PrimeSearch' for the project and 'Srsieve' for the sieving software. Separate each selection by a comma. (Obviously if you did an individual-k search on your own, then the software may vary.)
8. You should now have a new proof code and can submit the prime. Example...L442.

Step 3: Submit the prime:
1. Go to the home page in the link above and select 'Index' on the left side under 'Provers'.
2. Next to 'search proof-code', type your new code from step 2 and press enter.
3. Towards the bottom, next to 'Submit primes using this code as', click on your name (prover account) and press enter.
4. If necessary in the little pop-up box, type in your user name (prover account) and password and press enter.
5. You should see a big free-form box. Type in your prime (no spaces needed) and click 'Press here to submit these prime(s)'.
6. A verification screen will come up. If the prime is correct, click 'Press here to complete submission'.