How can I consolidate my credit cards without hurting my credit? (Are there any secrets to paying off your credit cards fast without hurting your credit?)

I have had one credit so far but my payments were not kept on this one card. So i have made my decision and that is to not apply for another one. What are some ways for me to build my credit without credit cards. I have my own apartment and my cell phone wit tmobile.
where are some places that i can apply for a car loan?

I’m trying to boost my credit score as much as possible. I have credit cards but find it harder to get loans due to my score. I need help figuring out a sure-fire way to gain points by using the credit that is already available.

i want to know how much should i spend on each credit and should i pay off completly or should i leave a few dollars on i heard that you should use 30% on each then pay off each month but leave 5 10 dollars so credit card company get some money . also will it hurt my score if i don’t use my 5 cards monthly? I only use my cards for bill, gas groceries ect. so i know i’m spending money that i already have. does any one know what are other things i can do to bring up my credit score. i have a 580 right now but i will be looking to get a house in a year or two so please if anyone has any ideas on raising my credit score pease respond thank you.