You are ready for a sexual relationship --with yourself!
Just as important as learning about a partner - what they want - want feels best - what does work --is learning those things about yourself.
What is the best thing to use? Your imagination!
For beginners there are two very common things to try first - water and fingers.
The pressure of water can be a wonderful feeling and you don't need to touch yourself or use lubrication--which when you first start out can feel a bit odd. Use the spray from a handheld shower of the flow fron the tub and direct the flow of water against your clitoris - or anywhere on your vulva. Wiggle about to see where it feels best. Don't use water too hot or pressure too strong.
Fingers are also great. usually it will feel better if you use a bit of lubrication on your fingers. Use your fingers to explore your body- your breasts - your vagina, your clitoris - where every your fingers lead you. Try touching yourself in different ways- soft/hard, slow/ fast, tickling/scratching.
When you're ready to graduate to using sex toys there are lots of different things on the market. You can also try using things you find at home - candles are good - but I recommend you cover them with a condom. What is nice about candles is that they are cheap, you can buy them in different sizes and they don't look like sex toys.
If you click on my sex toys link you can see some sex toys I recommend for beginners - plus the lube that I think is the absolute best.
Experiment and play - and know that nothing you do is wrong and that having a good sexual relationship with yourself is one of the nicest things you can do for yourself.