How to create dropdown menu in Homepage

you need to use wp-admin->appeareance->menus, to create drop down menu of your choice.

@slider by latest post.
enable slider in customizer->general->slider, enter any cat id and count number. and edit lib/sliders/jd-gallery-slider.php line 19

$query = new WP_Query( "cat=$featured_category&posts_per_page=$featured_number&orderby=date" );

to

$query = new WP_Query( "cat=&posts_per_page=10&orderby=date" );

edit the 10 to your own count.

Hi Richie,
I’ve successfully created a drop-down menu, thanks!
Can you please tell me where to locate lib/sliders/jd-gallery-slider.php ?
Also, I’ve noticed that after changing my theme to MesoColumn, my tiled mosaic galleries are not displaying correctly.
An example can be found here: https://fashionecstasy.com/2015-notable-awards-honour-millennials-in-30-industries/
Notice that the single image inserted are centred but all the tiled mosaic galleries are squished to the left and do not expand to the post’s whole width.
I have researched online and some say it’s because the theme does not define a width? I set my posts’ width to 600px in the custom css but it didn’t seem to solve the problem. Is there a way to make all my galleries expand to 600px so that it aligns everything else? Thanks.

the file located in themes/mesocolumn/lib/sliders/jd-gallery-slider.php.

@mosaic issue
a bug in this version, open themes/mesocolumn/functions.php, cut line 15
if ( !isset( $content_width ) ) { $content_width = 550; }
and paste to line 13

it should be outside of function mesocolumn_init_setup() {}

Yes! I fixed them both, thank you so much!!