Coloring Cloud Label

ADD above ]]></b:skin>

This for Fewer number of labels

/* Sidebar Label Cloud */
.sidebar .cloud-label-widget-content {margin:0; padding-left:20px!important;}
.sidebar .label-size a {color:#fff!important;background:#222;padding:8px 22px;margin:0 3px 3px 0;float:left;display:block;
-moz-transition: all 0.2s ease-out;
-o-transition: all 0.2s ease-out;
-webkit-transition: all 0.2s ease-out;
-ms-transition: all 0.2s ease-out;
transition: all 0.2s ease-out;
}
.sidebar .label-size-1 a {background:#FF8000}
.sidebar .label-size-2 a {background:#D7DF01}
.sidebar .label-size-3 a {background:#B40404}
.sidebar .label-size-4 a {background:#298A08}
.sidebar .label-size-5 a {background:#084B8A}
.label-size-1 a:hover, .label-size-2 a:hover, .label-size-3 a:hover, .label-size-4 a:hover, .label-size-5 a:hover {
background:#2288bb; color:#fff; text-decoration:none}
.sidebar .label-size span {
background:#2288bb;
color:#fff;
padding:8px 22px;
margin:0 0 3px;
clear:both;
float:left;
}
.sidebar .label-size {
position:relative;
text-transform: uppercase;
text-decoration:none;
font-size:16px;
font-family:'Oswald', sans-serif;
color:#fff;
}
.sidebar .label-size a, .sidebar .label-size a:visited {color:#fff;text-decoration: none;}



This is for Many number of labels

/* Sidebar Label Cloud */
.cloud-label-widget-content {text-align: left;} .label-size {background: #83B4D8;display: block;float: left;margin: 0 3px 3px 0;color: #fff;font-family: Oswald, Arial, Sans-Serif;font-size: 11px;text-transform: uppercase;} .label-size:nth-child(1) {background: #F86D9E;} .label-size:nth-child(2) {background: #37C371;} .label-size:nth-child(3) {background: #10BBEA;} .label-size:nth-child(4) {background: #25CBFE;} .label-size:nth-child(5) {background: #963690;} .label-size:nth-child(6) {background: #A3195C;} .label-size:nth-child(7) {background: #545454;} .label-size:nth-child(8) {background: #F2A15F;} .label-size:nth-child(9) {background: #00FF80;} .label-size:nth-child(10) {background: #B7860B;} .label-size:nth-child(11) {background: #99CC33;} .label-size:nth-child(12) {background: #FFFF3D;} .label-size:nth-child(13) {background: #3FDECF;} .label-size:nth-child(14) {background: #FF2F0A;} .label-size:nth-child(15) {background: #E9DB58;} .label-size:nth-child(16) {background: #42FFBD;} .label-size:nth-child(17) {background: #6899ED;} .label-size:nth-child(18) {background: #FF52AE;} .label-size:nth-child(19) {background: #8DBC2F;} .label-size:nth-child(20) {background: #80FF00;} .label-size a, .label-size span { display: inline-block; color: #fff !important; padding: 4px 10px; font-weight: bold; } .label-size:hover { background: #222; } .label-count { white-space: nowrap; padding-right: 3px; margin-left: -3px; background: #333; color: #fff ; } .label-size:hover .label-count, .label-size:focus+.label-count { background-color: #FF6BFF; }

DEMO : look right Sidebar