Example page with form elements for you to get an idea on how they look like.
All forms of the Joomla! core extensions should look nice with the stuff, but be aware not all other 3rd party extensions are following Joomla! standards.
Form Sample Code
<form> <fieldset> <p> <label for="input1">Sample Input 1</label> <br /> <input id="input1" name="input" type="input" /> </p> <p> <label for="input2">Sample Input 2</label> <br /> <input id="input2" name="input" type="input" /> </p> <p> <input id="radio-sample" type="radio" /><label for="radio-sample">Sample Radio Input</label> <input id="radio-sample2" type="radio" /><label for="radio-sample2">Sample Radio Input 2</label><br /> <input id="checkbox-sample" type="checkbox" /><label for="checkbox-sample">Sample CheckBox Input</label> <input id="checkbox-sample2" type="checkbox" /><label for="checkbox-sample2">Sample CheckBox Input 2</label> </p> <p> <label for="select">Sample Select Field:</label><br /> <select id="select"> <option selected="selected">Option One</option> <option>Option Two</option> </select> </p> <p> <label for="textarea-sample">Sample Textarea Field:</label><br /> <textarea id="textarea-sample" cols="80" rows="5">Textarea text</textarea> </p> <p> <button>Submit Button</button> <input class="button" type="button" value="Reset Input" /> </p> </fieldset> </form>