What skills are required for a PHP Developer?
Here are the following skills required to be a successful PHP developer.
1. Understanding of Web Applications/Services
PHP is primarily used to develop web applications and web services. So it is very much essential for a PHP developer to understand the scope, need and functioning of Web Applications in IT sector.
2. Client-side Scripting
PHP developer must have a good understanding of various client side Scripting languages like HTML, CSS, JavaScript etc. Because it may require to integrate PHP with these languages to build a powerful web applications.3. Database Concepts
As a PHP developer one should know the basics of database and the methodologies to integrate PHP with different database management tools like MySQL, Oracle, Postgresql, MongoDB etc.4. Frameworks Understanding
There are many PHP frameworks out in the market. PHP developer must have a good grip on atleast one framework. Some of the frameworks are Laravel, CakePHP, Zend, CodeIgniter, FatFree etc.5. Understanding of Architecture Pattern
Development will be easy and effective if any of the Architecture pattern is followed in the programming. As a PHP developer, one should have a better understanding of any of the Architecture pattern. MVC, MVVM etc. are few examples.6. OOPS Concepts
PHP follows many OOPS Concepts so as a PHP developer one should know the OOPS Concepts and how to use them7. Basic Knowledge of Linux, Apache and other FOSS tools and technologies
PHP can work in windows platform too with any other web server but majority of the development and hosting is done on Linux platforms with Apache server running on it. so a PHP developer should have a better understanding of that.What skills are required for Graphic Designers?
These are the 8 essential skills for every graphic designer to have, if you want to excel in a graphic design career!
1.Visual Ideation/Creativity. ...2.Typography. ...

3.Design Software (Photoshop, Illustrator, InDesign, etc.) ...

4.Color Theory. ...

5.Web Design/Basic HTML & CSS. ...

6.Layout/Conversion Optimization. ...

7.Print Design.
What skills are required for SEO Executive?
A. On page SEO Strategies
• Meta Tags Optimization (Meta Titles, Meta Descriptions & Meta Keywords Optimization)• H Tags Optimization
• HTML Code Cleanup & Optimization
• Site Content Optimization
• Anchor Text Optimization
• Internal Linking Structure and Site Navigation Optimization
• Creation of side & Footer links if needed
• Optimization of java script, flash which hinder in robots crawling.
• Image Alt Tags Optimization

• Error Page Configuration
• XML Sitemap Creation
• Static Sitemap Creation & Optimization
• Robots.txt Creation
• Should have preferably worked with eCommerce, WP, Joomla sites
• Knowledge of HTML 5, CSS
B. Off page SEO strategies
• One way Link building• Local / Niche Directory Submission
• Article Submissions
• Press Release Distribution
• Blog Postings & Commenting
• Classified Postings
• Guest Posting
• Social Bookmarking
• Back link analysis & research on link building techniques
C. Social Media Marketing
• Promotion on Facebook, G+, Twitter, LinkedIn, Pinterest• Promotion on YouTube and Other Video Search Engines
But above all I must say that the key thing required is the Passion to learn.
All the best.