They are to be found in many shapes and sizes. Some of them are made to resemble a penis and others are shaped in a practical way for general stimulation or for stimulation of specific points like the G-spot or the prostate. They can be made stiff, elastic or flaccid.
A vibrator is any vibrating device made for sexual stimulation. Often a dildo with an electric vibrating machinery inside is just called a vibrator.
Whatever your specific use, you should choose a dildo made of strong material, it should not have any sharp angles, it should be smooth and the parts of the device should be assembled together tightly and solidly. A flaccid dildo should not be too flaccid so that it does not curl up inside you. A simple and solid dildo is often better than many of the fancily shaped dildos you can get in the market.
If you are unfamiliar with use of dildos, it is best to choose a thin one as a beginners device. When you have more experience, you can gradually begin using thicker sizes. When doing so, you will often experience that the thick dildos do not necessarily give stronger feelings, but rather other kind of feelings, and therefore you will still have use for your thin dildos.
When using the dildo, either the dildo or your intimate opening should be lubricated with a good lubricant. Dildos made of latex or other elastic materials should be lubricated with a water-based lubricant since oils can destroy the material in these. Dildos made of plastic, metal or glassy materials are best lubricated with an oily lubricant.
A dildo used in the anus should never be used in the vulva or vagina afterwards without being washed well, since the female organs are sensitive to bacteria.
When using the dildo, set the tip against your opening and press gently so that it glides smoothly inside. Then you gradually insert it steadily deeper until it has come to the deepest point you want to have it. To increase the stimulation you can also insert it stepwise, by pushing it some way in, then pulling it a little less outwards again many times.
When deep inside, the most basic way of stimulating yourself is to repeatedly pulling it some way out and pressing it in again towards the deepest areas. Do so gently at first but gradually intensify your actions until your feelings reach a peak. Then relax some time and begin doing the same again.
If the dildo have capabilities of vibration, those can be used to add further pleasure. Screw up the strength of the vibration gradually until you find the strength that pleases you must. It is often very pleasant to just lay still some time with a gently vibrating dildo inside yourself and just feel the stimulation from the dildo.
You can also set the tip of the dildo against specific points. A woman having it in her vagina can point it upwards at the vaginal wall to stimulate the G-spot by massaging movements. A man having it in his anus can do the same against his prostate or just at the backside of his prostate. Both sexes have some very sensitive areas in the deep parts of the anus. Those areas actually give the greatest feelings by means of a very gentle massage and tickling with the dildo tip.
A couple can use a dildo as an element in the foreplay. You can begin by teasing up your partner with a gentle teasing and massage outside the intimate opening of your lover with the dildo. Then gently tease your lover further up by taking the dildo in and out several times, and eventually take it down to the deepest level s of your lovers inside and masturbate your lover internally at a deep level.